Playing friends in a private room in Mario Kart Wii WFC?

I want to play with three other friends that I already have registered. I have tried creating a room, and we have all entered the room, but i can not for the life of me figure out how to create a private race for just the four of us. why is this so confusing to figure out? The instruction book just says close the room you created?! Please help i am sooo confused!