schoolfights said:
To win a girl you need to be someone she can talk to, but talking doesn't do any good when you reply with a lie. Don't be afraid to tell her what you really think or how you really feel about her or your relationship.
No offense schoolfights, but this is exactly what DOESN'T work. I'm guessing you're a girl...never take advice on how to get girls from another girl! In other words...don't ask a fish how to fish.
In response to the question, you need to smile, say hi, and then flirt with her. What do I mean by flirt? Tease her playfully, if she's smiling and hitting you playfully, you're doing great. Then, you get her number, call her up sometime, and get her to hang out with you. From there, you escalate physically, until you get in there
I'd recommend reading the DJ Bible, there's lot's of good stuff in there that will get you started.