Katy Perry out in London on December 22, 2009 – photo: Ringo, Jesal Parshotam, PacificCoastNews.com

Sonia by Sonia Rykiel Sequin Star Dress – $235 [exact]
Armani Exchange Stars Sequin T-Shirt -$29 [cheaper alternative]

you can buy wristbands like this at lots of places, including Hot Topic:

Hot Topic Black and White Checkered Knit Wristband – $2.99

exact: River Island Panda Hat in Grey – sold out

similar: River Island Cream Knitted Panda Beanie – £12.99

thanks ThisHeartBeatsx

exact: Paper Route Heart Hoodie – sold out

Sierra Kusterbeck candid

Forever 21 Faux Leather Jacket – $38.90

exact: Ben Sherman Riley Coat

£50 @ Ben Sherman UK

£70/$118 @ ASOS

$160 @ Yoox

$162 @ Atom Retro

£95 @ Dress For Less

$229 @ Punk.com

ps. her hair is red again!

exact: This City Sleeps Swallow T-shirt – sold out

exact: BDG Wool Military Bomber at Urban Outfitters – sold out

exact: Girls ‘DBNO Santa’ Logo on Skyblue Melange Tee Shirt – £20

exact: Tripp Grey Skinny Jeans – sold out

similar: Tripp Cement Grey New Skinny Pants – $29

(you can see the Tripp logo on her back pockets)