How do I encourage him to ask me to make it official..?

I've been seeing this guy for a few months now. Lately we've gotten closer. We've opened up a lot more. And recently he told me he liked me. I told him I liked him too. When we're together we're incredibly close, and he's jealous a lot. Yet shy in an incredibly endearing sense. He's very attractive and tall. The control seems to be mutual. He's very busy and is away a lot playing rugby, but always makes time for me. We're basically together, but how can I make it obvious to him that it's what I want, and that he should perhaps initiate this kind of conversation to become 'official' if you like. There is no doubt in my mind that this is where it's going. I just need a structure and knowing that it's not just going to dwindle out. You know what I mean..