There are tones of tips, those two just happen to come to mind first ...
Dress comfortably and not over the top. Feeling pain because of those too fancy shoes or being afraid you'll show a builder's cleavage when you sit down, makes any woman look a little stressed out and the guy could think it's because of him.
Talk enough to give the other person a chance to know you but try to talk not as much as the other person. There is so much to tell about a guy if you listen to him for a while. If he is not worth it, you'll know it before you end up in bed, or even in a relationship with him.