Girls or guys look great with that high collar behind the neck on top of a flowing cape.
For the ladies in particular, the colors red and black work good, with a collar included as well, with a more feminine cape or dress with wide sleeves.
All fangs of course are appropriate for vampires, but you can get some extra long ones that really accentuate and make more believable the realistic look you're looking for. It's even deliciously creepy.
Whatever you choose, go with these ideas and you'll be sure to be a hit at whatever type of gathering you come to as a vampire.
Vampire makeup and costumes never fail to be popular, and you're sure to generate some chuckles and smiles as you display your dastardly self.