Katy Perry Practices Her VH1 Diva Salute for the Troops

Start getting excited! VH1 Divas: Salute to the Troops rehearsals are well underway and Katy Perry is practicing hard. 

OK! GALLERY: KATY PERRY IS PERFECT IN PURPLE FOR "PURR"

VHI1 Diva: Salute to the Troops airs Sunday, Dec. 5 at 9 p.m. and is hosted by Kathy Griffin.

Katy Tweeted a picture in costume with the "Queen of Comedy."

OK! NEWS: KATY PERRY & NICKI MINAJ SALUTE THE TROOPS

But Katy has been hard at work rehearsing with Keri Hilson and Jennifer Nettles and you can catch a clip of them singing along to "Boogie Woogie Bugle Boy" below!