If you start up a friendship with her, DON'T assume that she wants to move into anything else unless she indicates so. It may be that a romantic relationship naturally forms out of friendship, but if it doesn't then it's ok to step back and ask her out on a date - which is a frightening risk, but better than waiting and pining away hoping something will happen on its own. Unless you make it clear that you have romantic intentions, she may not know you're interested!

In general, I think it's a bad idea to try to get closer and closer to someone in hopes that romance will "just happen." Often times, that means that one person ends up feeling very hurt and upset if the other isn't interested, and just wants a close friendship. You sound like you'd like to be friends with her even if she doesn't want to date you - if so, and you're worried about things being awkward if she says no, I think the easiest way to make things comfortable is to very clearly say what you're feeling: that you are interested in pursuing something more, but if not then you are happy to remain friends. This gives her a clear choice as opposed to feeling pressured one way or another: it would be very hard to maintain a friendship she feels like the *only* way to stay on positive terms with you is dating you. If you make it clear that friendship IS still an option, there is a good chance she will take it. (This is assuming a worst-case scenario where she doesn't want to go on a date, but that doesn't mean this will happen of course!)

I hope that's helpful! I'm really shy too, and I know it's so nerve-wracking to be so open with someone you like, but it feels so good to get things in the open. Best of luck whatever you do!