You really can't go wrong except for just having your hands at your side. That's the one thing not to do. You can put your hands on his cheeks. You can put your hands on his other set of cheeks... You can grip his arms the back of his head. You can grab his shoulders. Wrap them around his back. You can grab (gently) his crotch. I like to graze my fingers down the sides of their bodies along the ribs because it's a sensual feeling.
Let me answer your question by asking you a question: When you're making out with your boyfriend where would you like to touch him? What parts of him seem like natural parts to touch while you guys are kissing? Don't overthink it but just picture yourself in the moment and do what comes naturally. And then when you're actually in that moment just touch him where you feel like touching him.