WITH AN EYE ON . . . : Angela Watson’s acting is a big put-on--and that fits the part just fine

Karen Foster is a conceited, bubble-headed, fashion-occupied teen.

Angela Watson, who plays Karen on ABC’s hit sitcom “Step by Step,” hopes that no one thinks she’s that airheaded.

She will reluctantly say she likes fashion a lot. Then, grudgingly, Watson, 18, adds that her parents tease her about looking in the mirror as often as Karen does.

Nonetheless, playing someone stuck-up is fun, Watson says from her San Fernando Valley home. “I think she really has feelings inside of her she sometimes lets show,” she says in defense. “She’s probably not that self-centered. It’s a show she puts on so she doesn’t have to show her true feelings.”

Watson--and Karen--have put on that particular show for three seasons. “Step by Step,” currently in summer repeats, enters its fourth season this fall.

The actress’ five-year career bio almost reads like a how-to manual for young actresses: beauty pageant winner to model to commercial actress to hit TV series co-star.

At 11, the Danville, Ill., native moved to Florida, where her farmer father had retired, with her mother, her brother Carroll, now 23, and sister Amy, now 26.

She won her first beauty pageant to become Miss Sunburst at a mall competition. Within two years, Miss Sunburst had 60 more crowns and 200 trophies vying for shelf space. The secret to her success? “I really wanted to do them, they were so much fun and I loved all the different outfits. We did a pageant every weekend.”

The pageants led to modeling. Two years after Watson was named Face Finders’ Model of the Year 1987, her family moved to California so she could begin an acting career. After a series of national commercials, she won a recurring role in 1991 on ABC’s short-lived “Davis Rules,” which starred Jonathan Winters.

While she can’t envision any other full-time career for herself, she’s got her sights on a secondary or alternative career as a country-Western singer. She turned to singing when her tap dancing wasn’t winning her the “best talent” trophy at beauty pageants.

“The singers would always beat me,” she says. But when she won that coveted prize in first attempt, she decided that country music suited her quite well, and that “what was missing in country music were kid singers. There isn’t anybody kids can relate to.” Watson hopes to be that missing link. Last weekend, Watson was scheduled to perform tunes from her upcoming country album at the California Strawberry Festival in Oxnard.

Even though the recent John Burroughs High School graduate’s busy schedule hasn’t allowed for much of a social life, she keeps her eyes on the big screen. Giddily, she says she’d really like to work with Keanu Reeves.

Since her show airs on Fridays, a popular night out, she says most of her classmates at high school didn’t even know she was an actress. But at local malls or appearances, children often beg for an autograph. “My mother always carries around these postcard pictures of me,” she says. “There’s a list of my favorite things on it, so they can get a lot of information about me.”

One thing not on the card is Watson’s “really intense” interest in acting classes, where “I read lots of things to get to know what our profession’s like, like plays and stuff.” Her bible has become Stephen R. Covey’s “The Seven Habits of Highly Effective People,” definitely not a book that “Step by Step’s” Karen would be interested in. “It’s the greatest book for everyone,” Watson insists.

“It’s really all about sacrificing now for the happiness you’ll want later.” And that, she adds, is exactly what she’s doing.

“Step by Step” airs Fridays at 9 p.m. on ABC.