How do I initiate sex with my boyfriend?

He's in the army, so we always go back to his barracks, and we start off by watching TV for like an hour before he gets up and iniates it. I'm a bit on the shy side but would like to surprise him one day by initiating it...I just don't know how without feeling stupid or embarrassed. So, guys, how would you want a girl to initiate sex with you? I mean what would be a good way?