Ever been out on the preach, and at somebody's door, and it's just gone very quiet inside and you know that there's somebody there but they're ignoring you? Be that guy.
Or, if it's more complex than that; say they've been sent by your folks, and they know you're there, and you have heard them, and you have to talk to them... be sick. Put on a robe or just strip down to your shorts and mess up your hair, like you've been in bed all day and you have to get back to it or you'll fall over.