Blowjobs... no seriously, one a day.

If you aren't in a sexual relationship. Just do things for him that he likes. If he likes a home cooked meal, cook it for him. If he sees admires something at the mall, and you have the cash, get it for him. If he is gonna be out when his favorite show is running, record it for him(Tivo!)

But most of all. Hugs and kissing. Just be close to him once in a while and don't worry about talking.

Thats all the advice I can give you sadly.