TUESDAY MORNING, President and Mrs. Carter will pack up.Their paintings of Georgia landscapes, and personal photographs; Amy's cat, Missy; Mrs. Carter's ballgowns -- and their memories of elegant entertaining will all go to their home in Plains, Ga. Mrs. Carter said recently, "Now we'll have to finish the attic to hold all this."

Hardly before the boxes are all out, the incoming President and Mrs. Reagan will move in with their Chinese porcelains, love for red decor, 20th-century design, and California taste.

The Reagans will have $50,000, appropriated each time White House occupants change, to do up the family quarters to suit themselves. If that doesn't cover it, they might be able to siphon a bit from the White House's annual general maintenance and repair budget of $3.1 million. Anything else will have to come from friends and supporters or out of their own pockets.

The Reagans can redecorate the family rooms of the White House to their heart's content -- paint the whole thing red, bring in 10-foot trees. Structural changes would be difficult and not possible without quite a hoopla, such as raised by President Truman's balcony.

President Carter last week gave credit to Chief Usher Rex Scouten and Curator Clement Conger for maintaining and adding to the White House's magnificance.

Scouten has made everything work since he became usher on March 1969, though he worked for the White House for several years before that. Scouten, an employee of the Park Service, takes care of the maintenance, the staff -- everything, indeed, except ushering. He's quiet, unobtrusive, and never, never tells tales out of school.

Clement Conger, the White House curator, is the man responsible for the decorating of the mansion. Conger, who also came during the Richard Nixon administration, has raised millions of dollars in gifts to the White House. He is also a civil servant by the way, though he and Scouten could be removed to some place else by a determined president.

A good many changes on the second floor would not be popular. The remodeling of the Yellow Oval Drawing Room, called by Nancy Kissinger "the most beautiful room in the world," was completed just after the Nixon resignation at a cost of $400,000. A settee and a matching pair of chairs, made in Philadelphia in 1805 for President James Monroe, were found by Conger in Houston. After a speech, a Monroe descendant came up to the podium and said, "I have some Monroe furniture that once was in the White House. Do you want it?" Conger said, "Sure -- if you can prove it." And she did.

The room also has a handsome Turkish Hereke rug and four French bergeres (armchairs). Foreign state visitors are entertained here for 20 minutes or so before state dinners.

The next-door Treaty Room was decorated in the Victorian manner during the Kennedy era. The Lincoln Bedroom and the Queen's Bedroom (across the hall from each other) each have small sitting rooms. The East Sitting Hall, between the two suites, was used as government offices for years. Sightseers, boon-seekers were free to wander in.

President Nixon used the Lincoln Bedroom as his private sitting room. He kept a fire burning in the grate even in summer with the air conditioning on. He smoked secret cigars in here. More than once he set off the fire alarm when he went to sleep and dropped his cigar on the rug. The other night, Amy and her friends tried to summon up Lincoln with a Ouija board there, but the only one who came was her Mother to shoo them out.

The other end of the second floor is more private, though rather cramped. The president and his wife, in recent years, have had three rooms as their very own. President and Mrs. Nixon originally used one as a bedroom, one as a study and a third as a dressing room. But soon, Mrs. Nixon moved out of their bedroom, into the second room, saying that the president liked to wake up in the middle of the night to read or work, and she couldn't sleep with the light on.

The Fords shared a bedroom, as did the Carters, using the other room as a sitting room. The dressing room is traditionally the first lady's. Each room has a bath.

The chief problem for the first family, according to Mrs. Carter, is to find a comfortable place to sit after dinner. They finally solved the problem with comfortable chairs by the fireplace in the president's study, with a shared ottoman. The Presidential Suite leads off the West Sitting Hall. Mrs. Carter, giving me a quick look, said one of her regrets was that she never had a chance to have the heavy draperies and curtains removed from its magnificent semi-circular window. Soft chairs and a sofa, a television set and bookcases are a help; but there are too many doors to be peaceful or private.

Across the hall from the president's rooms are two other bedrooms with a small passage between. Amy uses one as her bedroom and the other as her sitting room. A smaller room is used as the beauty parlor. Amy had a shampoo party the other night. The Kennedy children used the rooms earlier. Conger said he expects Mrs. Reagan will use the rooms as her office. Mrs. Carter has had an office in the East Wing, along with her press and social offices.

At the northwest corner are the president's dining room and small kitchen with a dumbwaiter from the ground floor. The dining room was converted by Mrs. Kennedy from a bedroom, because she found it awkward to feed the children on the State Floor in what is called the Family Dining Room.

Conger fervently hopes that the Reagans will like the wallpaper in the President's Dining Room: a copy of Zuber's 1834 "Scenic America" showing George Washington entering Boston in triumph in 1776 and an imaginary battle at Virginia's Natural Bridge. The paper was installed by Mrs. Kennedy, removed by Mrs. Ford, reinstalled by Mrs. Carter. "Fortunately," said Conger, "it's on linen, so it can be rolled up and stored. But it's hard on it."

On the third floor are two more guest suites, some service rooms. Best of all is the solarium where the Kennedy children had their school and Mrs. Carter had her Spanish lessons. Wayne Dean, Mrs. Carter's decorator for the room said it would be "too kind to call it awful -- all brilliant yellow walls" before he redesigned it in fall 1978. Mrs. Carter had the pleasant and sunfilled room repainted in an off-white and furnished with a glass table, a cabinets for the stereo and cane back chairs. The sofas and chairs were recovered in a soft blue, white and yellow. The adjacent tiny kitchen, used by the Carters for Sunday night supper, has new picture tiles. Next door, the billiard room has been mostly used for pingpong by the Carters. Jeff Carter says they all play, but "Dad's the best."

Recently, Conger took Ted Graber, Mrs. Reagan's decorator through the White House and then to the treasure house -- the warehouse where all the furniture and objects not now in use are kept. Conger said: "We have some beautiful things in storage -- as well as the reproduction B. Altman pieces that were bought during the Truman administration. I thought Mr. Graber knew a great deal about things -- though perhaps that's because he and I seemed to have the same taste. He selected several looking glasses, some tables and chairs -- he won't be able to use them all, but he'll see."

Conger explained that he has acquired as many alternate furnishings as possible so that they can be substituted when pieces have to be sent out to be reupholstered or repaired. A settee for the Green Room, for instance, is kept at the ready.

Conger said he sent President-elect Reagan photographs of the desks available for the president's oval office in the West Wing. "He chose to keep the H.M.S. Resolute desk," Conger said, "which I recommended. The desk has been used by President Carter and every president from Rutherford B. Hayes to John F. Kennedy."

The desk's brass plaque reads: "H.M.S.. Resolute forming part of the expedition sent in search of John Franklin in 1852 was abandoned in latitude 74 41' N. Longitude 101 22' W on 15th May 1854. She was discovered and extricated in September 1855 in Latitude 67 N. by Captain Buddington of the United States Whaler 'George Henry.'

"The ship was purchased, fitted out and sent to England, as a gift to her Majesty Queen Victoria by the President and People of the United States, as a token of goodwill & friendship. This table was made from her timbers when she was broken up, and is presented by the Queen of Great Britain & Ireland to the President of the United States, as a memorial of the courtesy and loving kindness which dictated the offer of the gift of the 'Resolute.'"

Conger said the Reagans have not yet had his grand tour of the state rooms, though he was on standby when the Reagans came to the White House and Mrs. Reagan came a second time with Ted Graber. "I suppose they didn't have time."

Conger said Graber was impressed by the quality of the materials used in the White House. As well he might be. This spring, new over draperies will be installed in the East Room and the State Dining Room. The fabric costs $300 a yard -- about $130,000 with labor for one room.

"The house has hard use," said Conger. "Replacements of draperies and wall coverings, upholstsery and such cost $400,000 a year. The Diplomatic Reception Room upholstery has to be replaced every six month; the Green, Red and Blue Rooms every two years. The draperies for those cost $10,000 a window."

The Red, Green and Blue Rooms, the house's formal parlors on the State Floor were redecorated to a design of the late Edward Vason Jones under Conger during the Nixon administration. The Green Room even then cost $485,000; the Blue Room, $292,000; and the Red Room -- Mrs. Reagan's favorite -- $170,000. Conger has just bought an alternate rug for the Green Room so the first can be sent out for cleaning. The new one cost $60,000, but green Oriental rugs are rare because green is the color of Mohammed's turban, and Moslems don't want to walk on it.

Paying for all of this isn't easy. Conger has raised all the money for the state rooms since 1971 when he was named curator. Finally, a year ago, "so that the first lady and the curator wouldn't have to spend all their time begging," Conger said, the White House Preservation Fund was established by Mrs. Carter. The Fund aims to raise $25 million so that new acquisitions to the house and replacements can come out of the interest. In a year, $1 million has been raised for the fund. The White House Historical Association, publishers of the four guides and sets of slides, have raised $1,216,000 for White House furnsihings during the Carter years.

Because of President and Mrs. Carter's great interest in art, "they really know and care about art," according to Conger, the emphasis has been on paintings, especially American Impressionists. A total of 33 paintings, 18 prints and maps, 2 drawings, and 2 sculptures have been donated during their administration. Also donated are, 7 documents, 12 pieces of presidential memorabilia, 7 chairs, 2 sofas, 12 tables, 1 case piece, 2 mirrors, 3 beds, 12 pieces of silver, 22 ceramic objects, 7 rugs, 2 textiles (including a bedspread for the Lincoln bed and a sampler), 2 lanterns, 4 chandeliers and 18 miscellaneous objects -- for a grand total of 168.

Conger said, "the Carters haven't been given credit for all they've done for the White House." He hopes now for more American paintings of the 18th and 19th century including paintings of the South and West. Seven portraits of first ladies have been given to the house during Conger's tenure, but seven more are missing: Mesdames John Adams, Thomas Jefferson, James Madison, Martin Van Buren, Zachary Taylor, Franklin Pierce, Andrew Johnson, Ulysses S. Grant, and Chester Arthur. The White House owns no life portraits of Mesdames George Washington, Andrew Jackson, Grover Cleveland, Herbert Hoover and James Garfield. As for presidential portraits, Conger is looking for ones of John Adams, James Buchanan, Andrew Johnson and William McKinley.

Currently, 61 pieces of furniture, 39 decorative objects, 140 paintings and 6 pieces of sculpture are on loan to the White House by museums, art galleries and private collections. Conger would like not to have to borrow.

The State Rooms now have some protection against passing presidential fancies. On March 7, 1964, President Lyndon B. Johnson established the Committee for the Preservation of the White House, which recommends "as to the articles of furniture which shall be used or displayed in the public rooms . . and as to the decor and arrangements best suited to enhance the historic and artistic values of the White House." But, of course, the president appoints the committee -- obviously one to suit his and his wife's taste.

Still, by a law passed in 1961, the furniture of historic or artistic interest becomes the property of the mansion, with the Smithsonian as the repository of anything not in use. This is to prevent several earlier disasters. For years the White House furniture was sold off as each succeeding president redecorated.Chester A. Arthur probably holds the record. He sold 24 wagon loads of objects called "decayed furnishings." According to "The White House, an Historic Guide," the 5,000 bidders in the East Room competed for "hair mattresses, marble mantels, curtains, matting, carpets, cuspidors, and an old globe of the world that once belonged to President Grant's daughter Nellie." One favorite story has that an auction offered the "trap that caught the rat that ate President Lincoln's hat."

Unfortunately, no one knows what happened to the famous Louis C. Tiffany screen of American eagles and flags "in the Arabian method," which President Arthur had installed in the entrance hall, nor the animal heads with which President Theodore Roosevelt enlivened the State Dining Room.

The collection on the ground floor of presidential china was started by Mrs. Benjamin Harrison, who discovered some of it in a closet. Harrison, according to the White House guide, was especially fond of the bathroom with its "white tile and marble and porcelain-lined tub. They would tempt a duck to wash every day."

Mrs. Harrison was the first to try to move the president's offices out of the east end of the second floor. She had good reason, since their family included 10 people. It was 1902 under Theodore Roosevelt before the West Wing of presidential offices and an east guest pavilion were built to a McKim, Mead & White design. The new construction swept away the greenhouses that had been part of the White House since 1857.

The architects also found, on investigation, that the house was in bad repair. The drains were hollowed logs, for instance. It was all reconstructed at record speed. McKim's simple, classic design for the East Room is still followed today. The third floor, remodeled built out of attic space, was organized by Ellen Axson Wilson.

Grace Coolidge was the first to ask Congress to authorize the acceptance of antique gifts for the house. Mrs. Hoover catalogued the White House furnishings. The Franklin Roosevelts redid the East Wing with three stories of offices and a bomb shelter. In the East Wing is also the movie theater -- Reagan should enjoy that. President Truman added a balcony and then found out that his daughter's piano was about to go through the floor. The whole house was gutted and rebuilt.Conger likes to say that the White House has been destroyed three times -- twice by fire and once by the Army Engineers.

Mrs. Kennedy began the redecorating of the modern White House. Mrs. Nixon completely redid the three parlors. Mrs. Carter added pictures, antiques and initiated the Preservation Fund.

As for entertaining, every President and First Lady have their own styles. Jefferson had people turn up to feast every night. James and Dolley Madison gave Wednesday "drawing rooms." President Nixon had prayer breakfasts on Sundays. President and Mrs. Carter have put their spotlight on the great performers in classical music at elegant Sunday afternoon musicales and State Dinners. They have also had informal barbeques and picnics, with country music, as did the Lyndon Johnsons.

The Carters, people who have a real understanding and appreciation of art, have also used American crafts to embellish the house. Gretchen Poston, the social secretary, had decorated the Carter Christmas trees either with antiques, which are crafts of another day, or present day crafts. Mrs. Carter also commissioned American potters and glassmakers to make table settings for a Congressional lunch, and often used quilts as tablecloths and museum objects as centerpieces.

Presidents, first ladies, first children, first cats -- they come and they go. They put up and they take down. Some have taste. Some don't. But the White House's tall columns stand serene, waiting for the next term.