How can I get my bf to miss me or to cling to me more?

Both 17 and have been dating for a year. In the past month or so I have noticed that he seems to be less interested in me. I think it's because he knows I miss him a lot and that I am readily availiable whenever he wants. So I'm wondering, how can I act so he misses me? Because he never says "I miss you". Also, when we do hangout how can I make him want me more? I've never been good with "leaving him wanting more." how can I do that?