The best thing to do is look like you want to be kissed. Try to be as open and approachable as possible for him. Think of it as giving him the courage and the key to kissing you.
Try a little touch of the arms or shoulders here and there. It can be a very simple gesture and very quick as well. No need to make a big deal out of it. Touching can help bring him and you into a more intimate state.
You should look at his lips. This is a very clear sign that there is some kind of attraction between you. You could look at his eyes to make sure he is looking at you and then his mouth and back to his eyes. Also, smile after you do to make it even more clear (especially if he is one of the slower homo sapiens). This should be a hint to him if he is up for it.
Try moving in to a more personal bubble. If you get in close to him he will have less distance for the travel of his lips to yours. The closer the better.
If he is still not getting the hint (and there are some who do) simply go in a little for the kiss or just kiss him yourself