Tina Fey Tina Fey

Before Mom Jeans became a catchy jingle and a fashion don't on Saturday Night Live, they were simply Tina Fey's last-minute clothing solution.

Fey tells Vogue she first came up with the idea for Mom Jeans after she had a fire in her apartment and had to buy a pair of emergency jeans for work one day. "It was right before the low-rise thing kicked in officially, and I inadvertently bought these jeans, and they had this enormous rise," Fey says. "And I was going around the office complaining about them all night, joking about it, and Maya Rudolph and I started singing a little Mom Jeans song. We just goofed around, and I wrote that up very quickly."

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The 39-year-old Emmy winner, jokes the first step to the memorable skit was the hardest. "The first step was admitting I had on Mom Jeans."

Since the Mom Jeans skit, Fey has undergone a major makeover and fared well fashion-wise as she won many a Hollywood award.

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Fey credits her increased fashion knowledge to the costume designers at SNL and 30 Rock and says she sticks to a few simple rules when dressing for the red carpet. She says she tries to stay healthy, but does not weigh herself and now knows the power of double-stick tape for a plunging dress. Fey also says she's learned to lean towards dresses with a deep V neckline and away from spaghetti straps.

"Because every person, no matter who you are — how tall you are, how short you are — some things work on you and some things don't. I don't like to wear things that feel like costumes," she says. "I have learned enough that I can go to a rack and say, 'That's not going to work. That's going to work.'"