I don't know very much about your situation, but if he allows you to stay at his house, I'm sure your relationship is pretty good. Just get physically close to him and flirt a lot without going overboard on giggling, doing stupid things, and the like. See what happens when you do that is all I can say right now. Although I don't advise on making too many obvious advances in case he doesn't have feelings for you.
Also remember that if things do go too far, you have the right to tell him to back off. Don't submit to everything he wants just because you like him. It kind of makes you come off as someone who doesn't have a backbone and that tends to make others lose respect for you. Plus you are entitled to go as far as you want without him pressuring you.
I hope things go well.