You're 27 years old, newly married and despite your two incomes, after paying the rent on your small one-bedroom apartment, there doesn't seem to be much left over to furnish your home tastefully and comfortably.

Or perhaps you're new in town, just moved cross country from Los Angeles and have sold all your furniture in the process. You settle in an efficiency in downtown Washington within walking distance of the new job. Where do you begin designing your bachelor/bachelorette pad?

Or maybe you've divorced and the other partner got the furniture. You get the cat but there's no place for either of you to purr. You've found a condominium that's just the right size, but you and the cat are starting from scratch.

Sarah Jenkins, director of the design department at W & J Sloane, and her interior design staff think they have the answers -- or at least some suggestions.

The designers at Sloane's have been holding a series of three one-hour workshops at each of their branch stores -- the last will be held this week (Aug. 12, 13 and 14) at White Flint.

Carol Donnelly, interior designer with Sloane's and coordinator of the workshops, started off the seminar at the Connecticut Avenue store with the basics. "There are many kinds of furniture, but for our purposes we'll divide them into three main groups: traditional, contemporary and a mixture of these two, which we'll call 'eclectic,'" says Donnelly as she points to a chart showing specific styles and periods.

Donnelly feels lifestyles have changed since the days when you couldn't mix a colonial sofa with a modern glass table or have a floral-print bedspread with striped curtains. Things are less rigorous now. "Your home should reflect who you are." A good way to discover who you are, suggests Donnelly, "is to note what kind of clothes you wear. People who like warm colors wear reds and browns. Others prefer cool colors such as yellows and greens."

Three tools of design are important in designing your place: color, furniture styles and how you put the furniture pieces together.

"People seem to have the most trouble with color," observes Donnelly. "The stark white walls of your average apartment can make your furniture look dull." She recommends a coat of paint, a borderline molding trim or hanging decorative sheets to bring your furniture to life.

Colors can either blend or contrast. Blending colors are centered around a basic hue -- blue-violet, blue and blue-green. Contrasting colors, on the other hand, are opposite each other on the color wheel, such as green and red, blue and orange, yellow and violet.

In addition remember that color, like design, should give a feeling of organization. According to the chart on color at Sloane's workshop: "In color as in design, an underlying sense of order is satisfying. But stereotyped, common-place organization is tedious."

Organizing your furniture is another decision you must make. You must decide what your needs are. If you often work at home you may want to portion off a corner of your living room for a desk and files. If you entertain much you need to arrange your chairs and tables so people can mix and mingle. And for display cooking -- as with woks or crepes -- you may want a long, formica (even marble) buffet in the living room to show off your culinary skills.

Efficiencies, one and two-bedroom apartments are examined in the Sloane seminar.

Sloane's recommends flexible furniture that you can use later in many different ways in a larger house. In their model efficiency, the full-sized posturepedic convertible sofa ($500) can be used in your next place in the guest bedroom or in a den.

Using less expensive outdoor furniture inside is a designer idea used here with a dinette set made up of elegant Brown and Jordan lounging chairs ($100 a piece) and a matching 46-inch round table ($225) -- all bordered in brown metal. When you have your bigger apartment, you can move it out to a patio or porch. The two square, brass-legged bunching tables with glass tops ($130 a piece) can be pushed together as a coffee table, or be used separately as end tables or even as night tables in the bedroom.

The other model rooms at Sloane's are expansion possibilities as you move up in the world from an efficiency to a one-bedroom, a two-bedroom and eventually to your dream house. The packages that Sloane's has put together for each of the above are moderately priced -- at least by Sloane's standards. Their furniture package for an efficiency is under $2,000 which includes the sleep sofa and Brown and Jordan dinett set, as well as two end tables, a cocktail table, and a wood caned-back armchair with a velvet seat.

The one-bedroom apartment model uses the efficiency list plus an added bedroom suite, adding $1,000 to the cost for a total of $3,000. The alternate full-sized living-room design -- done in either of two styles, contemporary and traditional -- costs $2,000. (This living room package replaces the efficiency living room, so the total cost of the one-bedroom package remains at $3,000). and a formal dining room, which seats six for dinner and includes an etagere , costs an extra $1,000. All the models could eventually fit into a full-size house.

Sarah Jenkins points out that many of the designers who worked on the model rooms are young and just starting out themselves. "We were really able to identify with the choices faced by other young homemakers who have limited funds and limited space, but still like good merchandise," said Frederique Georges, a design intern from the University of Virginia.

For many of the workshop participants this was the first time they had worked with professional interior designers. "What we hope to show them," says designer Donnelly, "is that designers can help you live in the most comfortable way you can. And, we designers will work with limited price ranges as carefully as we would with more extensive budgets." Two Plans for Efficiencies EFFICIENCY PACKAGE No. 1 Total: $1,813 1. Full-size Sealy posturepedic beige nylon sofa - $500 2. Pecan wood wicker arm chair by Lewittes - $235 3. Pecan wood end table by Lane - $135 4. Pecan wood square cocktail table by Darnel - $125 5. Semi-circle chrome glass end table, by Swaim - $193 6. Brown and Jordan round dining table - $225 7. Brown and Jordan lounging chairs, four at $100 each - $400 EFFICIENCY PACKAGE No. 2 Total: $2,892 1. Queen size 80-inch convertible sofa by Karpen - $650 2. Velour cushioned Colony House armchair - $225 3. Rectagonal mappa burl wood end tables, two at $130 each - $260 4. Brass-trimmed glass bunching tables, two at $248 each, by Swaim - $496 5. Pecan veneer card table (38-by-38 inches), by Lane - $247 6. Pecan wood high back side chairs with cotton velvet seats (four at $144 each, by Lane) - $576 7. California/ASIA etagere - $375 NOTE: The prices, are nearly all sale prices, pointing out how much you can save by being careful when you buy. The design plans do not include accessories such as lamps, rugs, posters, pictures, curtains. Objects borrowed from your home or accumulated from four years of college dormitories, things you've collected from junk shops, garage sales and antique shops will soon make your place reflect your taste.