Dont use any stupid lines, just be yourself.If you approach a group make sure you dont alienate..introduce yourself to the group as a whole, doing this will get you into that circle of friends and make it 50x easier to score that 1 girls number you're looking to get with. If shes alone, just be yourself, introduce yourself and start conversation but DO NOT spend all night sitting there just talking with her..make your move for the number or take her home or something or other.If you wait like 3 hours talking to her chances are nothing will happen.Also before going up to them, make eye contact but not the creepy kind..just enough to snag her attention.