SPOTTED! “Gossip Girl” costume designer Eric Daman showing the must-have fashion trends for your closet — and the show — in 2010.

Gossip Girl‘s costume designer Eric Daman has spilled the beans on what the future holds for Serena van der Woodsens and Blair Waldorf’s closets in 2010.

Those who tune in to “Gossip Girl” on Monday nights do so not only for a “look inside the scandalous lives of Manhattan’s elite,” but also for the fashion.

The man responsible for the fashionable ensembles, which usually amounts to about 80 costumes an episode, is Eric Daman, head costume designer and stylist extraordinaire for “Gossip Girl.” Now the man who launched a thousand trends is letting the world in on his secrets in the new style book “You Know You Want It.”

Eric Daman lives a fashion lovers dream with walls of beautiful bags and stunning shoes to choose from when dressing the hip cast of the most fashionable show on television. From high end designer duds (Valentino 360 tote, YSL Roady bag) to emerging designers, Daman has been responsible in outfitting the cast in their signature style. “It’s a fantasyland to have fun in,” says Daman of the drama series.

The show’s wardrobe closet, hidden inside a warehouse studio in Long Island City, is full of handbags (organized by color), boxes of shoes (organized by size) and baskets of headbands (for Blair!), bow ties (for Chuck!) and drawers of tights, gloves and everything in between. FASHION HEAVEN!

Daman invited The New York Post into the most coveted dressing room in town to talk trends for this year. “Instead of compiling your list of perfect must-haves solely from the mannequins in shop windows,” he says in the book, “see what experiences you have had that make you unique, and then incorporate them into your personal style.”

“The book is a motivational fashion book,” said Daman. “I wanted to give back to the girls who watch the show.” What fashion trends we can expect from Gossip Girl when the season returns March 8th? “The statement bracelet,” revealed Daman. “That’s my big tip!”

STATEMENT BRACELETS

“It’s all about mixing materials. Enamel pieces are also going to be big,” Daman says. This MCL enamel flower cuff (left) is $2,190; this Stephen Dweck oxidized sterling silver and turquoise serpent cuff (right) is $3,865.

EXPOSED ZIPPERS

Daman says he’ll add a zipper to a piece if the fit isn’t right. “Only if it’s something minimal so I don’t toy with the design,” he says.

PAINTED PRINTS

“It’s almost Monet-like. A real concept,” Daman says. Jessica Szohr (Vanessa) is wearing a dress by Diane von Furstenberg, $425.

British designer Erdem has also designed a brilliant collection of painted prints, which we could see on the Gossip Girls.

TEXTURED TIGHTS

“Men love them. They’re really sexy and a nice take on a contemporary fishnet. For the winter, put a nude tight underneath to keep you warm,” Daman says. Taylor Momsen’s character Jenny is wearing a Yigal Azrouël coat, $1,092; Magaschoni scarf, $198; D&Y beanie, $20; DKNY tights, $20.

GRAY

“The new interpretation of gray is that it’s the new black, a neutral. It’s a no-brainer,” Daman says. Blake Lively’s character, Serena, wears a Philip Lim coat, $650, and a Carlos Falchi “Brooke” bag, $4,995.

STRUCTURED

“This is very minimalist and linear. It has a Bauhaus architecture sense to it. Its lines could be those of the Chrysler Building, or the downtown Washington Square arch with the structure of the Upper East Side,” Daman says.

In January, Eric Daman celebrated the launch of his new style book at NYC department store Henri Bendel with the fabulous cast on hand to lend their support.

Leighton Meester (who wrote the book’s foreword), Blake Lively, Jessica Szohr, Michelle Trachtenberg and Ed Westwick dressed in their hippest finery to toast the man who provides their unique characters on the CW show with a style all their own.

Daman doesn’t just cover outwear, but also the much needed (and often overlooked) subject of underwear. “Underwear and breasts and bras and things that can push and pull,” he explained. “Spanx are on the set every single day,” Daman dished. “Who’s wearing them, I’m not gonna tell you.”

“I’m a girl from Wisconsin,” Jessica Szohr said. “Everything I know about fashion is because of Eric and Gossip Girl.”

Considering fashion was the topic of the night, “Gossip Girl’s” leading disappoint in that department displaying an array of attire as versatile as the characters themselves.

Leighton Meester, the Queen Bee of sophisticated style, wore a look straight off the runway from Louis Vuitton’s Spring 2010 collection: a fuchsia-lace-trimmed floral skirt, textured gray jacket, and sheer pink shirt.

Blake Lively shut it down in a Nonoo Lyons black tuxedo jacket paired with a simple while button down shirt and Stella McCartney’s thigh-skimming perforated boots.

The $1200 boots, made from faux leather, give the illusion of a legging, but with a shoe attached. The show-stopping leg wear has been seen on Rihanna as well as Stella McCartney herself.

Jessica Szohr plays hippie-chic Vanessa on the show, but opted for simply chic in the perfect LBD by Alice + Olivia by Stacy Bendet ($198). Jessica paired the form fitting Tabitha dress, with mesh back, with black platforms for a smoking hot look.

Michelle Trachtenberg also donned a LBD, but took a more feminine approach in a Rag & Bone Spring 2010 belted frock with plunging neckline. Her statement necklace provided the perfect accoutrement to the ensemble.