Ok. I've been a member for about a year, and have gotten some good advice, so I'm going to contribute back. Here's a trick that I actually tried:
1. Get alone with her (obviously)
2. Get a conversation going then somehow find a way to tell her she is pretty. Don't chicken out. Don't think about it, just do it when the opportunity arises. I don't know what it'll take to get to that point, but once it does, do it.
3. Whatever happens next, I leave to you and your girl.
If you're wondering, I don't know what happened in my case. She just kinda said, hm. I got a hug later, but that was a different thing.
-College