How Many Fittings Did Jennifer Lawrence Need to Co-Host the Met Gala?

Today, Jennifer Lawrence boarded a plane for New York City, just days before she co-chairs the Met Gala on Monday -- a gig she's taking seriously.

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"I think it's going to take 45 to 46 fittings and I have a rough idea on the dress," J. Law said. "It's very exciting."

While the opportunity is one that many would die for, J. Law explained how she almost let the chance of a lifetime slip by her.

"I got an email and I didn't reply to it because I never do, and then I started getting pressure to respond," she said. "Then I was like, 'Yes! I'd love to!' and I really didn't know what I said yes to, and now that I know what I said yes to, I'm thrilled."

Last year, her friend and Silver Linings Playbook co-star Bradley Cooper co-chaired the event with Sarah Jessica Parker. She revealed the practical advice the American Sniper star had to share.

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"He just told me to wear comfortable heels, because last time his feet hurt," the 24-year-old actress said.

Since she is the face of Dior, it seems like a safe bet that she'll be wearing a creation from the French label.

Marchesa is another go-to fashion house and designers Keren Craig and Georgina Chapman chatted with ET about Blake Lively's gown from 2010, which was archived at their New York showroom.

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"Blake Lively's dress was blue, short textured embroidery," Chapman said.

"It was straight from the runway actually," Craig added.

For Marchesa, it's common practice for gowns to be returned and archived for future photoshoots, but they have made exceptions.

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"One of the only times that we've given up a dress was when Sandra Bullock won an Oscar in a dress that we made for her," Craig said. "So obviously we wanted her to keep the dress."

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