I really like this girl. Please help me?

I've been talking to this girl for a few months now and we've hungout a few times. We talk a few times per week over text, but I'm always the one who texts her first. She always responds and we almost always have a good conversation. She's nice, she's pretty, she's funny, she's athletic... I could say a lot more. Anyway, she's never had a boyfriend before and is more on the quiet side when we hangout. But she still tells me after each time we hangout that she'd like to do something again... I've told her I think she looks beautiful and I've complimented her in other ways. I've flirted with her a LITTLE bit, but not too much. But I just don't know how to tell her I really like her or to make our relationship as more than friends. I think right now she's interested in me and I'm interested in her, and we have never been completely in the friend zone so I don't have to worry about that.. I'm pretty smart, I play sports, I can have a sense of humor, I'm nice, and pretty caring.. I look at least average, maybe slightly above it. I think she knows that I really like her, but she hasn't made any real advances with me to make me think that she also really likes me. I would like to take her to prom this year (I still have just under 4 months though) and I have a plan to do that, but I would prefer to be boyfriend/girlfriend with her before then so we can really have a relationship, and then asking her to prom would also be easier. What can I do to make her like me or like me more, as more than a friend? Or in other words, I think she has a little interest in me but what can I do to peak her interest and make all of this work? I'm really nice to her and as I said, I text her first, a few times per week (I'd like her to text me first though too)... But what can I do to spark her interest and actually be something with her? She means a lot to me, so if you can help me it work this out it would mean so much to me!