Jessica Simpson keeps it old school when it comes to documenting her red carpet extravaganzas.

The 35-year-old fashion designer took ET for a ride along with her while on her way to a red carpet event celebrating the 10-year anniversary of the Jessica Simpson Collection, and she revealed that her red carpet ritual is taking a Polaroid selfie.

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"It's actually something that Eric created," she said, crediting husband Eric Johnson. "He loves a Polaroid picture, so I always know that an authentic Polaroid picture looks amazing - mainly because my husband took it, but it looks good."

Keeping with the old-school trend, Simpson's style icon is a real throwback.

"My style icon is definitely Brigitte Bardot," she said. "I always end up pulling up inspiration and it's a Brigitte Bardot pic. I always want her hair. I want her eyes. I want everything about the Brigitte Bardot look."

One of Simpson's biggest tips from her bag of tricks is to get plenty of rest.

"The secret to getting red carpet ready is to take a nap before you get your hair and makeup done," she said.

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Simpson can rest easy knowing that her business is booming. Last year the brand banked a reported $1 billion in sales.

"I could not be more proud of this moment," Jessica said of her brand celebrating a decade.

Despite Simpson's success, she hasn't lost track of her priorities.

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"My biggest success in life is being married and having babies," she said. "The fact that I can have some sort of normal home life, I think that's the best."

She added, "My husband is the best support that I could ever ask for. He's even wearing a little bit of blue in his tie tonight, so that's a big deal. We're kind of matching. To get a man to do that is hard to do, so that's good support."