share a sense of humor and never bring up an ex
you have to act like a girl but have a guys sense of humor then you win
The quickest way to a man's heart (barring surgery) usually involves some sort of food...
But seriously, following Kiteman's advice should put you well on your way to a less awkward relationship.
Act natural, don't be too touchy-feely. Find something you can both talk about (even if you aren't interested, it gives him a distraction from his shyness).