Work on your conversational skills. Also you've got to be fun. you're lucky you've got height and good looks. Those are the things that are for the most part out of your control.
The things you're lacking (confidence and social skills) are actually things you can work on and develop.
Also if your goal isn't to find love and all you want is casual sex then Whoever cares the least wins. You need to have the mentality that you would like for a girl to have sex with you but really don't give a shit if she says no. If you want her more than she wants you then the power dynamic is in her favor and conversely if she wants you more than you want her then its in your favor.