What are some of the best ways to impress a girl you like?

I like this girl alot and we are just friends right now but I think that she has a thing for me because everytime we are together and I say something funny she touches me when she laughs and when I dont pay her any attention she says that she misses me, but when I try to ask her out on a date she rejects me so how do I get out of the friend zone? Should I even bother to persist and look for someone else?