So there's this girl called Vanessa and I really like her but I'm not sure if she likes me or not. We hangout at lunchtime sometimes but not that often and I really like it when we talk but I'm scared that if I ask her out and she rejects me than we won't talk at all because she'll feel uncomfortable around me knowing that I like her and I REALLY don't want that to happen so what should I do? By the way I haven't given her any reason to think that I would like her.

Try to get to know her a bit better then bite the bullet and ask her out on a date.

I agree with amcon. Get to know her better. Suggest hanging out more often. Weisle your way into her life and make her think about you more. But also keep yourself a small distance and don't be flirtatious. If she thinks you're interested it might scare her and if you act too much like a friend that is all you'll ever be seen as to her. Try and stay kind of mysterious but at the same time get to know her. Ask questions about her and talk about her. Don't open up too much yourself and if she asks you a personal quesiton use your judgment. If you don't think its vital that she knows what she is asking you to tell her don't tell her. Just say something like Well that's a long story. If she says OK tell me anyway, just say I don't feel like getting into it right now. Don't be appologetic cause that'll show weakness and let her know that she can get it out of you. Just drop the subject and move on. It seems kind of mean I know but women like a guy to be a little on the unknown side.