I see her as the kind of girl to have ginger hair, although I don't know why. For her costume, though... not sure. If I were you, I'd work on the things you know first, so do the skin etc. Once you've got that done, the rest might come to you a little better. Sort of like dressing yourself - people know what they look good in because they know what their skin tone, hair colour etc. is.

Maybe someone can give better advice than me. =x