The struggle for the heart and mind of the man who would be President Reagan began within hours of his election as governor of California on Nov. 8, 1966. It is still going on. If Reagan's record is any guide, it would continue every day he is in the White House.

Every president charts his own course in the White House once he gets there, and it is speculative to say precisely what his policies would be ow how he would operate the executive branch. But there are signposts along the way. Based on his record in public life, especially eight years as governor of California, this is how Ronald Reagan would likely proceed if he should become president.

By its very nature, Reagan's mind is a natural background for those who would shape the future. He has strong convictions, a sense of history and some idea of what he wants to accomplish. He also has relatively little knowledge of the working processes of the government, and tends to be weak on details. He is a natural delegator with little concern about how departments are operated or who plays on the White House tennis court. He is likely to listen to whoever comes along.

When Reagan was governor of California, things rarely were what they seemed. He declared his feet were set "in concrete" against state income tax witholding, then agreed to it when he was persuaded the state needed more money. He campaigned for economy in government, yet sponsored the largest tax increase in California history. He ran against the redwoods, but his administration compiled a better-than-average conservation record.

As to advisers, there were many. In two campaigns for governor and 2-1/2 for president, Reagan had five different campaign managers. He had three different people in the key California post of state finance director, two of them able and all with different views.He had three chiefs of staff.

Sometimes, on difficult decisions, Reagan listened to key staff members.

Sometimes he even left the decision to them. Sometimes he listened to his wife Nancy. Sometimes he paid close attention to the views of the bureaucracy he had inherited from the Democrats; other times he ignored the bureaucrats. Sometimes the wealthy backers in his "kitchen cabinet" proved decisive with him; other times they couldn't get to first base.

What has been going on in the Reagan presidential campaign in 1980 indicated that very little has changed.

Early in this presidential campaign Reagan shunted aside one of his most trusted and capable California advisers, Michael L. Deaver, at the behest of campaign manager John P. Sears. Three months later he fired Sears.

A laundry list of 67 "foreign policy advisers" released by the Reagan campaign recently ranges from key advisers to persons Reagan has barely met. The Reagan list of economic advisers reads like a roster of every economist who has ever advised a modern Republican administration -- Arthur F. Burns, William Simon, Milton Friedman, Alan Greenspan, George Shultz, Charles E. Walker, Martin Anderson, Arthur Laffer, Jude Wanniski. If you ask Reagan, he will tell you he values them all.

The supposed economic battlelines for Reagan's allegiance were drawn by Wanniski in a recent Village Voice interview where he describes himself, Laffer and Rep. Jack Kemp (R-N.Y.) as the "wild men" favoring the "supply side" economics doctrine of reducing taxes to increase productivity. (For excerpted text of the interview, see Page F1).

"The opposing camp is an official board of advisors," Wanniski said in the interview, ticking off Burns, Friedman, Shultz and Greenspan and Casper Weinberger, former federal budget director. "It's a force to be reckoned with. They are more or less in a position of arguing caution.

Later he added, "If the wild men prevail in the battle for Ronald Reagan's mind, and if Reagan prevails in the fight for the nomination, the voters in November will at least be facing a real choice."

These are the key elements of Reagan's economic program in 1981, as envisioned by Wanniski in the interview: " . . . A 30 percent reduction in marginal income rates at 10 percent a year, indexing the tax system to offset future inflation; elimination of the gift and inheritance taxes; abolition of the windfall profits tax on the domestic petroleum industry; reform of the central bank to restore a convertible dollar -- gold exchange rates."

Many of these programs are compatible with the ideas Reagan held before he ever met Wanniski or Laffer. He has been urging tax reductions to encourage productivity for a quarter of a century and he won rousing ovations in the farm belt four years ago when he called for inheritance tax repeal so that farms could be handed down from one generation to another. He also has long favored indexing, although his first and biggest tax measure in California did not index and also raised the minimum inheritance tax.

Reagan did not enter office, however, with a secret plan to raise taxes and he is serious now about wanting to reduce them. As in California, however, he is likely to evaluate the economic situation in which he comes to power and base his actions on what the experts tell him at the time.

Which experts would he listen to? If the California record is a guide, he would listen to all of them and wind up with policies that would fully satisfy none. Even in adverse circumstances, Reagan keeps his broad goals in mind, which means that he probably would try to phase in some of his economic plans while postponing others.

While Reagan is attracted to supply side economics, he expounds with equal force in nearly every speech the traditionalist budget-cutting views of such men as Simon and Burns. In 1973, Reagan proposed a California constitutional amendment limiting government spending. He called its defeat "the greatest disappointment" of his governorship.

Reagan as a president would probably do a lot of different things, Including some that don't crop up in his campaign speeches. His personal memory of the Depression is strong, and he doesn't think that everything his early hero Franklin Delano Roosevelt did about it was such a bad idea.

"When you look back in hindsight, the WPA wasn't the boondoggle we said it was," Reagan said in a 1973 interview with "Human Events."

He may have been thinking of his father, whom the Works Progress Adminsitration rescued with a supervisory job during the worst of the Depression.

Above all, Reagan is a political pragmatist, a trait that clashes with his ideological campaign rhetoric. It is an attribute highly valued by Reagan's chief of staff, Edwin Meese, who is probably Reagan's closest adviser.

"It's better to get some of your programs than none of your programs," says Meese. "And occasionally you're going to give the other guy some of his progams in order to get some of your programs. Gov. Reagan would not do that if it meant violating basic principles, but he understands the need for realistic compromise that advances his program without sacrificing principle."

It is this quality of compromise that in California irritated people on the far right side of the Republican Party. Early in Reagan's administration, state Sen. John G. Schmitz, who once quipped that he had "gone pretty far in life for a Catholic Bircher with a mustache," broke with Reagan on economic issues. He helped commission a book called "Here's the Rest of Him," which describes Reagan as a closet liberal.

If his governorship proves a model, Reagan in the White House would erlcome a wide range of information but would want it effectively summarized. William P. Clark, his second chief of staff, devised a series of one-page, four-paragraph "mini-memos" on various issues that devoted one graph to his statement of the issue, another to the facts, a third to discussion and a fourth to conclusion and recommendations.

One longtime aide gives this run-down on what he considers to be Reagan's strengths and weaknesses:

Strengths -- Reagan has trong beliefs and is decisive.He wants candid opinions from his aides. "I didn't ask you to come here to be yes men," Reagan used to say to his cabinet officials, and there was a rule in the cabinet that no one mention the effect an issue might have on Reagan's political future. He had the ability to go to the heart of an issue, even if he didn't know the details. And he could communicate his philosophy to the public.

Weaknesses -- "He was Mr. Nice Guy with his people to a fault," accepting staff work that should have been rejected. He was not demanding enough of those who worked for him. Nor was he skeptical enough about the information he received. "If he wants to believe it's true, he doesn't question it." He wants to please eveyone.

Reagan does not agonize over decisions, some would say he does not agonize enough. But Meese believes that one of Regan's strengths as an executive is that he can make a difficult decision and go on to the next one without second-guessing.

Perhaps this trait is because Reagan appears to be a basically happy and secure human being. There is a masculine, Will Rogers quality about him -- he likes most other people and is usually liked by them in return. Reagan was no football All-American like Gerald R. Ford, but like Ford, and unlike Richard M. Nixon, he made his college football team. There are not apt to be any bunkers in a Reagan White House. Nor would he be likely to hide from Congress, the press or official Washington.

Some of Reagan's friendliness is as natural and homespun as the way he occasionally drops a "g" at the end of a verb in the manner of smalltown Illinois. Some of it was learned by careful observation in his chosen profession of acting.

"It has taken me many years to get used to seeing myself as others see me," wrote Reagan in his autobiography, "Where's the Rest of Me?" "Very few of us ever see ourselves except as we look directly at ourselves in a mirror. Thus we don't know how we look from behind, from the side, walking, moving normally through a room. It is quite a jolt."

Reagan's ability to see himself as others saw him was a big help to him in forming a working relationship with legislators -- as it would be with the Congress.

But Reagan did not start out well with the legislature, in part because he is quickly bored with political small talk. Once he learned to relax around legislators and tell stories the way he does with everyone else, he did better. Legislators who dealt with him came to like Reagan, too, because of his friendliness and because he kept his word.

One of the staples of Reagan's campaign speech is that he didn't get the legislature to "see the light but made it feel the heat" with direct television appeals to voters. Like many Reagan stories, this is a correct statement much exaggerated in the telling.

As long as he was beating upon the legislature on television, Reagan found it understandably difficult to get much of his program through. He did much better in his second term when he learned to work with the legislature, rather than against it. Almost certainly, as president, he would try to forge some working relationship with congressional leadership of both parties.

These are some of the actions that might reasonably be expected in the early days of a Reagan presidency. He would:

Carry out his promise to impose a hiring freeze at the outset, as a means of reducing the federal workforce by attrition. Since this is one of the few "quick fixes" that had much of an impact in Sacramento, Reagan can be counted on to try it again.

Make some symbolic declaration about the federal budget -- and quickly abandon them if they failed. In January 1967 he announced a 10 percent across-the-board budget cut in California, then restored the money two months later when it became evident that this was impractical.

Make some blunder at a White House press conference revealing ignorance about a major federal program. He would correct it the next day on national television, winning plaudits from the public and editorial writers for his forthrightness.

Name a lot of businessmen to high government posts and turn others loose in task forces to rummage for waste in goernment. One or two of the businessmen would turn out to be spectacular duds who would either quickly leave government service or fail to be confirmed by the Senate. Several others would surprise the press and their own bureaucracies by proving capable administrators.

Name a number of defeated Republicans to important posts.There would be a cabinet position for John B. Connally, if he wanted it, and maybe one for George Bush. But Reagan's appointments to the Justice Department would be based on merit and largely devoid of cronies.

Give "cabinet government" a try. The weekly cabinet meetings would be actual working sessions in which abler cabinet members would be working overtime to capture Reagan's allegiance to their pet proposals. Meaningful decisions would be made at these meetings.

Try to work through the Department of State in foreign policy operations, sharply reducing the size of the National Security Council staff.

Most probably, when announcing a new weapons system or some other military development, couple it with a peace gesture in an effort to demonstrate to U.S. allies that he is not the bellicose warmonger some of them believe him to be.

One of the greatest dangers in the early months of a Reagan administration would be his own rhetoric. He is given to verbal flights of fancy which could be perilous if U.S. adversaries took them literally. In time, presumably, they would also learn that Reagan tempers rhetoric with reality.

The best example of Reagan's realism in California came in his long struggle with the University of California over the issue of tuition. "Free tuition" was a battle cry of the university, even though it was something of a misnomer, and Reagan was determined to bring the university to heel and force a tuition charge.

After months of posturing on both sides, the issue came to a vote before the university Board of Regents, of which the governor is a member. Reagan said it would be "hypocrisy" to call tuition by any other name and insisted on a vote on the issue. He lost, 14 to 7.

After a long, private lunch in which he and the regents lobbied each other, Reagan came back with a new proposal, calling tuition a "charge" and earmarking the proceeds of such charges for scholarships and capital construction. It passed, by voice vote.

"If he walks like a duck and quacks like a duck, it must be a duck," Reagan said to aide Lyn Nofziger after the decision.

It was incidents like these that formed the pattern of the Reagan governorship. Beneath the ideological exterior was a practical -- and capable -- politician who understood the necessity for compromise.

Reagan would be 70 years old within a month of his inauguration as president. It is most unlikely that he would embark on a brand new pattern of decision making. The lesson of his governorship is that he would strike the best bargain he could, whether it was with Congress, with the bureaucracy, with American allies -- or with the Russians.

No doubt, the rhetoric of simple solutions and absolute alternatives would continue, as it has from the first days of Reagan's political career. But if the past is a guide, that rhetoric would be submerged in the political reality that goes with being president.