BY DESIGN : Not Your Father’s Seersucker . . . : . . . Or His Bald Spot . . .

Last summer’s “Forrest Gump” white-sidewall haircut has given way to this summer’s cine-cut--the “Casper” and its slightly fuzzier brother, the clipper.

Blame the rage for boot camp ‘dos on close-cropped Bruce Willis, Andre Agassi, Live lead singer Ed Kowalczyk and Bat Boy hunk Chris O’Donnell. Each has recently gone from hirsute to hair lite.

The prematurely bald and nearly bald cuts come in many variations--none forthe meek.

The clipper cut leaves less than half an inch of hair all over the head. Some salons charge full fare, $45 and up, and it needs maintenance every three to four weeks.

The Gillette Trac II home version cut is much less expensive, but extreme. A safety razor removes all the hair.

Model Richard Salgado, cut off all his hair last year. “I cut it to get jobs,” he says, and it worked--sort of. “I get jobs because of this cut. I lose them too. But that’s OK. The jobs I like are the ones where they ask for [this cut].”

He says it takes five to 10 minutes three times a week to scrape his head clean with a razor.

For high rollers, $75 can get a cut that is similar to a mother cat’s tummy: It looks as if kittens have been sucking on it. This salon style--a multi-length ragged crop, often bleached, then gelled to a vertical crispness--is highly desirable, reports Paul DeArmas, owner of Hair at Fred Segal in Santa Monica.

Lenny Strand, owner of Coif in Los Angeles, says he noticed the increase in requests for short cuts when Willis began making the talk show circuit and sporting a completely shaved head (for his convict role in “Twelve Monkeys”).

Few people have what it takes to go completely bald, the clipper wielders say. It has nothing to do with the shape of your head, the amount or color of hair, or your sex. Attitude, they say, with a capital A, is the key.

“It’s a street-tough-vibe kind of thing. People who have it can carry it off,” DeArmas says.

Even drop-dead-handsome guys have to have the attitude, says Cameron Smith, booker at Prima Model Agency.

Willis, star of three “Die Hard” movies, doesn’t have true attitude. And it showed on a recent taping of David Letterman’s show.

Letterman was so captivated by Willis’ shaved noggin that he felt compelled to draw a large happy face on it. An obliging Willis went along with the joke. Imagine Letterman taking a marker to Charles Barkley’s head. Impossible.