I guess the normal tell-tale signs would be, talking to the girl more texting more wanting to meet more than normal. It's almost like a 6th sense you just kind of know they're interested sometimes. I guess it works both ways from guys and girls. More
im in a situation at the moment where i think this chap likes me and the signs i think show that are
1) he has made a real effort to make sure im going to the events hes organised
2) he offers to give me a lift
3) he has made it very clear that he doesnt have a girlfriend
4) he asks me questions about myself and listens to the replies
of course i may be totally wrong and hes just being friendly.............. but im taking it as interest and will react accordingly !!! wish me luck cos he is nice !!!