OK! Exclusive: Jessica Simpson's "Fashion Star" Protege Reveals Behind-the-Scenes Secrets

What's it like to compete on national television with some of the best designers? David Appel just ended his three-show run on Fashion Star, and he spoke exclusively with OKMagazine.com about his experience.

The 34-year-old designer, who creates preppy clothes with an edge, was a part of mentor Jessica Simpson's team. "It was non-stop 18-hour days," the creator of the men's clothing line Cohesive & Co. tells OKMagazine.com. "I was up at 6am and done at 10-11pm, rushing from here to there."

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The grueling schedule was worth it. "Fashion Star made me a designer," says Appel, who graduated from UCSB with a degree in finance and fine arts. "It was like going to fashion school since I never went."

And Jessica proved to be a "helpful" teacher. "She knows what sells," Appel says.

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But behind the scenes, Jessica had to use fiance, Eric Johnson, as her muse.

"It was tough because Jessica has never done men's clothing, so she went on about what Eric would wear," admits Appel.

"The crew saw that John Varvatos could really help me out, so he started advising me while on the show. That was fantastic.  His advice was amazing."

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So what's next now that Appel's gotten great direction from two of the show's top-notch mentors?

Oh, Appel's been bitten by the show-business bug, too. "Now I want to do TV," he laughs. "Loved being on TV."

Who do you think will go furthest on Fashion Star? Tell us in the comments section or on Twitter @OKMagazine