Well if she really likes you, you have nothing to worry about really

But even when you're not sure - you should never fear rejection..Even if you are the most attractive man in a room, with the most addictive character,best dressed e.t.c -whatever ; chances are not every woman in that room will like you, because everyone likes different types of men. Rejection shouldn't be taken as personally as it is, and hence shouldn't be as feared (my humble opinion).
Now you're in an easier position,you know she likes you..There are several ways you can do it. One way I do it is while im hugging a girl and we let go, I rub my cheak on hers while we pull back..but really slowly, and then we get really close to each other. and you pause when you're face too face and really close. If she doesn't pull away(which she won't in your case), then you kiss her slowly..
Other ways from a hug, just start slowly kissing her neck and work your way up to her mouth(thats probably not too romantic of a first kiss though)..
Or if you do couple stuff like lie together in bed and talk..and she's facing you, just find the appropriate moment and do it.
It's only the first kiss that's a hurdle..She's probably as excited and wondering when you're going to kiss her.
Good luck mate