Please help! how do i start talkin with this girl on facebook that i like?

about a month a go, i commeted on this guys ststus, then this girl that idk did, she then aded me and strated talking 2 me through facebook chat, we talked 4 a few minutes. idk how 2 strt talking to her, shes on of the hottest girls iv seen, how 2 start talking how can i strat talkin 2 her agian?