If she a shy girl, than she will look at you and as soon as you looking at her she will look away, sometimes I ignore the guys because I don't wanna show that I'm interested, if the guy come up to me and start talking to me I most likely be nice or sometimes quite and sometimes if I'm really nervous I will say stupid stuff... lol here is another think you can check, touch her like in her arms and see how she react if she jump back for a sec that mean She like you.... I know all this don't make sense, but that what I do when I like someone... I hope I helped you.