It depends on the guy, for me: I love long hair on a girl, I think it's very sexy when a girl has long hair that goes to the middle of her back (It's very feminine). I also love tattoos on girls, typically small ones. A sense of style. An open, outgoing and spontaneous mindset. A girl who is not involved in drama and is not in other people's business.
Turn-offs: Short hair, unpainted nails, wears no make-up at all. dresses like a prep, carrying around small dogs, narrow-minded, Paris Hilton mentality, drama queen, cares about everyone besides herself, facebook/twitter junkie.