The real Edie Sedgwick had a streamlined mod style that, despite its extremity, ultimately looked very sleek and pretty sophisticated, but still fun and young. She knew that wearing a pair of huge earrings was awesome as long as the rest of your look was simple, and that she could pull of lots of thick black eyeliner and wearing long t-shirts as dresses. She looked very 60's, but in a unique, New York-y, Factoryish kind of way. Sure, Edie was of dubious talent (though I highly recommend her biography Edie: An American Life) but she had a lot of style.
Sienna Miller, or whoever costumed her, on the other hand, made this Edie's clothes look like one of those "1960's girl" costumes you can get at the Halloween superstore- I'm surprised they didn't include a pair of white platform vinyl go-go boots to go with her million necklaces, huge earrings, floppy hats, copious amounts of eyeliner that she can't pull off, and, yes, open-toe boots. I have to say this picture probably horrified me the most. Who was responsible for placing that horrible hat and cheesy Halloween-ish looking sunglasses on her head? Have they ever looked at a picture of Edie Sedgwick?
In conclusion, there are lots of things terribly wrong with this movie. Weezer plays The Velvet Underground. Hayden Christensen plays Bob Dylan. Jimmy Fallon is in it. I believe Mary-Kate Olson has a cameo- perhaps as a starving monkey, which is the only role I can see her successfully filling. Basically, there's nothing good. On the plus side, it could be really bad in a good/entertaining way. The clothes, however, are just bad in a bad way.