SUIT YOURSELF THIS YEAR'S SWIMWEAR LETS YOU SHOW A LITTLE ... OR A LITTLE LESS.

Byline: Barbara De Witt  Fashion Editor

Swimsuits are finally for swimming.

Oh, sure, the silhouettes are very much like those worn by pinups of the past - with bandeau and halter necklines and jungle prints - but the fabric and fit make these suits worthy of a comeback.

Instead of the usual viselike grip of a gidle, designers and manufacturers have figured out how to offer support and sex appeal with advanced fibers, hidden panels and a variety of new bra styles.

The trend reflects the undeniable fact that the average American woman is not a model's size 6, says Robinsons-May fashion director Milinda Martin. According to national statistics, she's a size 12 or 14, and that's good news to a lot of baby boomers who no longer feel comfortable in the string bikinis of their youth.

``We don't want to age, and we're fighting it tooth and nail, and the industry has had to adapt to that fact,'' Martin says. ``The tankini, which has been a big hit, is a perfect example because it offers the feeling of a two-piece without exposing the midriff. ... And this season, the top is even longer ... and then there's the newest variation called a skirtini, which is a tank top with a short skirt.''

Designers have also perfected old-fashioned ruching or shirring and given new life to some old fabric faves of the '50s. The trend is ``the look of something that once was'' suggests Mervyn's fashion spokeswoman Kate Rice.

She uses Gloria Vanderbilt's new modest two-piece suit as an example, describing it as having a '40s-inspired silhouette with a halter neckline and a tie in the front, a '70s black-and-white floral design and a jerseylike fabric.

Classic styles, but the fabrics have given them a new-found popularity, says Liz Claiborne designer Lisa Pikul.

``We went through flat tricots in past years, but we're having a huge success with thicker, texturized fabrics such as pique or faille (pronounced ``file'') because they conceal figure flaws,'' she explains.

Lands' End spokeswoman Jamie Schrandt is really sold on faille. ``The vertical ribbing has a slimming effect, and now there's a touch of Lycra for control, but not so much that it feels like a girdle,'' says Schrandt.

Other companies such as Calvin Klein, Jones New York and Tommy Bahama are powerizing pique and jersey with advanced fibers such as Tactel and new blends of spandex and Lycra because they've found that bumps and bulges are less noticeable in a matte finish than in the traditional shiny fabrics.

Look closely at the new suits and you'll also notice slightly lower leg openings and slightly higher arm holes, wider straps and more strategically placed design elements from racing stripes down the sides to a zipper down the front to give the illusion of a longer, leaner body.

Martin also sees the separates business growing, with more brand names and more choices in two-piece suits. Besides a choice of sizes for top and bottom, women can decide how much coverage or cleavage they want and can even mix and match colors and prints.

Regardless of the style, suits have also become multifunctional. When covered up with a matching sarong, skating skirt or long pants, they can go to the gym or a night club.

About our model

NAME: Lisa Guerrero.

Born in: Chicago, but grew up in San Diego and Huntington Beach.

Lives in: Studio City.

Profession: Sports anchor of Fox Sports Net's ``Best Damn Sports Show, Period'' and host of Cox Cable's ``Charger's Magazine.''

Personal stats: 5 feet 8 inches; size 8.

Marital status: Single.

Education: Attended Golden West College, Huntington Beach.

Best-known for: Making Dennis Rodman cry by calling him selfish and for her exclusive interview with Barry Bonds and how he dealt with death threats.

Favorite sport/team: ``I love baseball and the L.A. Dodgers. My dad (Walter Coles) and I bonded at the Dodger games and that's how I learned about the sport.''

Favorite Valley hangout: The Dari boutique in Studio City.

Personal interests: Salvation Army, Mothers Against Drunk Drivers, and workouts in batting cages.

Acting credits: Aaron Spelling's ``Sunset Beach,'' with guest roles on ``Frasier,'' ``Fit TV'' and ``Sport Geniuses.''

SINK OR SWIM

Flatter your figure with these tips from swimsuit experts:

--Have patience. You may have to try on 15 suits before you find the perfect fit.

--Start with a suit that's one size larger than your clothing. Then do a couple of jumping jacks in the dressing room to make sure that you don't fall out of the suit or that it's not so tight that it pinches your skin.

--Always check your rear view before purchasing a suit.

--The bigger the print, the bigger you'll look.

--Bandeau tops will make your shoulders appear broader; halter tops will narrow them but will also minimize hips.

--Matte fabrics hide figure flaws, while shiny fabrics expose them.

--Waist-line toners include hidden control panels, strategic color blocking and diagonal stripes.

CAPTION(S):

6 photos, 2 boxes

Photo:

(1 -- cover -- color) ON THE COVER

La Perla's decorative black suit is elegant enough for poolside parties and the club scene.

(2 -- color) Lisa Guerrero goes for the Americana look with a string bikini from Frederick's of Hollywood.

(3 -- color) Liz Claiborne's tropical print in pique fabric takes inspiration from the '50s, available at Gottschalk's and Robinsons-May.

(4 -- color) ``It's like something from a '40s movie,'' says Guerrero of this jungle-print suit by Body I.D., available at Robinsons-May.

(5 -- color) Guerrero reflects on the '70s in her Lands' End tankini, made of faille, the season's most forgiving fabric.

(6 -- color) Gloria Vanderbilt's modest two-piece suit combines a '40s silhouette and '60s print, available at Mervyn's.

David Sprague/Staff Photographer

Makeup and hair styles by Miriam Vukich of Factory Artists of Hollywood; Poole Cosmetics.

Location courtesy of Stephen Botte.

Poolside furniture provided by Orange on Beverly.

Box:

(1) About our model (see text)

(2) SINK OR SWIM (see text)