I've got a ton of answers for you cuz I went through what you are trying to figure out a while ago... Number one it has to do with the place that you are trying to meet girls. ie. a bar/dance club will be different than if you were say, in a grocery store or library.

The second thing I've learned my friend is that over 80% of human communication is non-verbal ie. eye contact and gestures. If you see a girl looking at you in a club and you look back just check out her eyes... give it a minute or two and look back to see whats going on and chances are if she is still looking your way she is interested.

Last piece of advice is that girls will not and believe it is not their job to approach a guy unless it is with a posse of other girls behind her. So what that means for you is that you have to muster up the courage to start "small talk" with a girl who is interested in you. This can be anything from, "so who is your favorite character of cheating housewives... or the simpson's etc..." You have to get her to open up before you can even think about progressing to the other stuff.

As long as you present yourself as a confident person that is comfortable walking over and starting a conversation with her chances are you will hit the jackpot my friend. Hope this helps