Take his face with one hand (on his cheek) and direct it towards your own. There is no mistaking this gesture but it leaves open the opportunity to turn you down without too much hurt pride. You can guide it in and it helps with control if you feel awkward.
Look at him in the eyes, you should know by the vibe you get from that if he wants to kiss you or not, if he's giving you "that look" then you must make the move, or maybe he will first.
