To have a conversation with her, i would go up to her and say, hi i am david. dont ask her for her name. that seems desperate. Wait for her to give you her name. Then find out what she likes. Find a common interest and talk about it. Then if your lucky and she likes you, ask her on a date sometime.
Just casually "bump" into her and make whatever is in her hands fall out and be like Oh sorry! and wile you are picking it up be like i don't think we have meet.... I'm ______ whats your name? and presto!
What a girl likes in a boy is how cute they are their persanallaty a sence of humor make her laugh and try to touch her shoulder when you talk to her and get to know her and her friends if her friends like you then she will like you if you are nice to her friends more of them and her will like you that's what I think since I'm a girl I would no about this stuff girls like it and boys don't no what girls like we don't like when boys try to act cool and when they make mean jokes about us and try not to be dirty about stuff