Clothing designers keep their wardrobes workable and simple

Many of America's top fashion designers are not clotheshorses.

Some of them have been wearing the same clothes for 10 years. Others wear the same outfit every day. One designer doesn't own a ball gown or even a silk dress.

Donna Karan, one of the two designers behind the Anne Klein label, likes to keep her wardrobe simple. ''I see so much change that my life must be simple,'' Ms. Karan says. ''I fall in love with a silhouette and proportion and wear it every day.'' Sometimes she relies on T-shirt dressing. ''I have tons of T-shirts which I wear with pants. I wear cotton ones in the summer and cashmere in winter. They're easy to pull on and they're comfortable,'' she says.

For evening, she still keeps it simple. ''I might wear black Garbo pants with a white silk shirt, sandals, and a good belt.'' Although she is invited to many black-tie evenings, she doesn't own a ball gown. ''I've never worn a ball gown, '' she says. ''Even silk dresses are not for me.'' Her jewelry includes two gold cuff bracelets, gold earrings, and a cowboy-like lizard belt that she teams with both daytime and evening things.

Ms. Karan, who is a striking 5 feet 8 and likes clothes that move, advises women to buy the best they can afford. ''Make it quality, whether it's shoes, a silk shirt, a great belt, or a handbag.''

Pearl Nipon, director of design for Albert Nipon (who happens to be her husband), doesn't like to fuss with clothes. ''I like things that just fall into place and are easy to wear,'' she says. When she commutes from her home in Philadelphia to her New York office, she uses an easy wardrobe plan. ''I wear the same thing for both days, and I take along an extra pair of shoes . . . that's it,'' says Mrs. Nipon, a trim size 6 who runs six miles each day.

''For spring I wear lots of knits. They're feminine and soft. I've always been a dress person,'' says Mrs. Nipon, who was credited a few years ago for getting women out of pants and back into dresses.

She places great importance on fine fabrics. ''Fabrics must work, and be year-round. Look at wool - it's not confining. It has longevity except for July and August. Silk is all year,'' she explains. ''Even cotton has a long season.'' There are no extremes in her wardrobe or in her collections.

''Today's women reject extremes,'' she continues. ''They've learned much about fashion and quality. They're true connoisseurs. With the opportunity to wear the same dress they see on Mrs. Reagan or any other fashion elegante, they keep informed,'' she says. (Nancy Reagan owns several Nipon dresses, including the much-photographed one-shoulder white organdy.)

Designer Pauline Trigere admits to owning lots of clothes, but points out that she has collected them over the years. ''Clothes are like good friends,'' says Mrs. Trigere, who wears a seven-year-old black mohair cape. She finds capes comfortable and owns them in everything from wool to fur.

Since she travels a great deal, her main concern is that the fashions work. ''Clothes must serve me well. If they wrinkle, out they go,'' she says. She sometimes designs special things for her trips. ''I decide what is to be my favorite color for the next season, and then I do a few things for myself, too, '' she says. ''I may design four or five pieces in purple - a skirt, jacket, trousers, a long skirt. I like to be practical.'' Her favorite dress is done in different colors. ''Actually, I have a form-fitting wool dress in four colors with big, matching scarves. They're good for air-conditioned places. I dress to my look, with no frills,'' she says.

For jewelry, she wears a favorite ring with an armful of gold bangle bracelets. Since turtles are her trademark, it's not unusual to see two gold turtle brooches on her lapel or even on her hem.

Mrs. Trigere is praised by retailers for consistently producing high-quality fashions. ''I've always tried to design clothes that women could keep in their wardrobes for years,'' she says. In private life, she enjoys being a hostess and cooking elaborate meals in her Manhattan apartment. For weekends at her country home in Connecticut, she favors pants and turtlenecks.

Carolina Herrera, a relative newcomer to Seventh Avenue, has just launched her third collection. ''I have many different styles in my wardrobe, but my favorites are all two-piece things. For summer, I like French linen, because it's heavy and doesn't wrinkle,'' says Mrs. Herrera, who like other designers is a collector. ''I have some dresses in my closet that I've had since I was 16. I don't wear them, but I keep what I like.''

The Venezuelan-born designer also likes pantsuits, ''although my husband doesn't like to see me in them,'' she admits. For evening she wears glamorous, feminine dresses in velvet, a fabric many designers now consider appropriate year-round. She gets excited when she talks about her passion for shoes. ''I must have 50 pairs - some are rather exotic looking. I love shoes and feel that they are a finishing touch,'' she says. ''And you can be sure that I never try to match the shoes to my handbags.'' That's frowned upon in the fashion world.