Someone tell me what I should do about this girl kinda long?

So I meet this girl through some friends of ours anyways she's pretty nice and cool to talk to I like her but she doesn't know it anyways she had a boyfriend for like 2/3 months anyways they broke up and I was there for her tried to tell her all the rights things, well I guess I said then to well and now she has another boyfriend, but we text all time and I mean all the time she's always flirts with me during this messages an I do it back all the time ibwas going to tell her I liked her but I really didn't get a chance to before she got another boyfriend and I really like this girl a lot what should I do?