What looks good depends on the girl. A good tactic is to look up a celebrity who looks like you, and mimic her. I'm a Caucasian guy and I adore cute white girls with dark brown or black hair that goes down past shoulders, preferably to the middle or the upper back.
Hair style... again, depends on the girl, and your face shape. No matter what girl though, guys love a cute, happy smile. Not a smile like 'smile for the camera' and smile like someone just told a funny joke or you saw something humorous.
It depends on the girl. I generally prefer shorter hair on a girl, but some girls just can't pull that off. As far as how a girl does her hair - I don't like anything that is trying to make her look like a kid (I can't stand bows and ribbons and sh*t). Color - again, some girls can pull off some colors, some can't. Most obvious is girls who dye their hair blond who don't look good as blondes.
Also not a big fan of styles that really pull a woman's hair away from her forehead. It just makes her look like she has a huge forehead.
I like wavy hair just slightly wavy I think if it's just straight it's pretty plain and bland. And for do's I like all kinds of braids and buns with chopsticks,lol I try to pick the ones with pretty designs on them, you can find some great accessories for you to put your hair up with. <3