Help?

I've been knowing a guy for over 2 years he was my first. And we've been having sex on and off. recently he's been very flirty (something that he's never done) I get along with his family so I've been over his parents house several of times. He now has his own place he asked me to come over which I have no problem with. I've never been over a guys house so what do I do? What do I wear?