How can I look like Blair Waldorf?

I'm so excited that Gossip Girl is back on Monday! It's mindless and stupid, I know, but i love it! Anyway, my friends and I are having a GG viewing party and we're all coming as characters from the show. So basically I have to look like Blair Waldorf. How do I do my hair like hers and what should I wear? And make it realistic people, I can't go shopping.