Help?

I know a lot of you are going to call me stupid, for a variety of reasons, but here's my issue. So I've been approached by a fallen angel who has been given the chance, through rebirth as a human, to return to regular angel status. To do this, myself and 3 other witches must set him free. He wants us to bind the circle. Now I've never heard of binding the circle except on Secret Circle, and TV shows aren't exactly reliable. So I guess I'm asking who knows anything about binding circles? Was it ever legitimately done? If so, how does one go about doing it? If it wasn't, that's great help too.