Josh Duhamel and Fergie on Dec. 31 at LAVO Photo by: Denise Truscello / WireImage

With her wedding only a few days away on Jan. 10, Fergie is busy tightening and toning her body to make herself look a little more Fergilicious in her wedding dress.

And it's been no easy task after being forced to gain weight for her role in the upcoming movie, Nine.

"It's hard, I've been working out every day," she said before her New Year's Eve concert in Las Vegas at The Venetian.

Her pre-wedding workout routine: "A lot of hiking and doing a bunch of sit-ups, working my butt off and just, you know, try to maintain and stay healthy."

The Dutchess showed off her body at the Vegas concert and later at LAVO where she celebrated 2009 with fiancé Josh Duhamel.

Before the clock struck midnight, Fergie was planning their New Year's Eve kiss, telling reporters, "Josh is definitely getting lipstick on his face and maybe his neck."

At 12, the couple was spotting locking lips in a deep kiss on the club's catwalk. Then, at their VIP table, they snuggled close to each other while sipping champagne and talking to friends before leaving at 1 a.m.