Advice for remaining time with boyfriend before his deployment?

My boyfriend is going on deployment in a couple of weeks. We’ve been dating for almost 3 years and this will be our first time being apart for longer than a week. We have an amazing relationship, so I’m not worried about him or our relationship. As for the deployment, he’s been wanting to go on one since I met him, so I know it’s a big deal for him. Any time he talks about it with me, I remind him that I’m happy for him and he deserves to go! The only thing I’ve been struggling with is the time we have left because I don’t want to “waste” it. He’s going to be gone for 10 months and I obviously know he’s coming back but every time we do something or even plan something, I have the mentality of, “this is the last time we will be able to do this activity till he comes back.” I will be able to talk to him and visit him once while he’s on deployment, but again I’m really only stressing about the time we have left. Any advice? Or maybe even some suggestions for things we should do with the little time we have left? I’ve heard about those matching bracelets and lamps that light up to show that you’re thinking about them, but I don’t know if they work well. What are some things that you wish you did with your partner before they left?