I want to have but at the same time I want to wait to get married?

I've been steadily talking to the same guy for almost 1 and 1/2 years and we are serious. He's talked about marrying me but I don't know when. We might just do it legally. I'm going to visit him this summer and stay at his place. He's 30 and has a job and I'm 21 almost finished college. AGGGGGH I don't know how long I can wait, lol.