I do mine backwards from most people. Instead of making the "circle" turn part using the elevator when the wings are perpinduclar to the ground - I use the rudder while the plane is inverted and upright.

Just started out that way to learn it. After you get that down and it's rough, but a true rolling circle then you start blending all the controls together as you go around so that it smooths out.

Have a plane that's set up good to begin with, if it's nose heavy getting a good rolling circle is very hard because the nose wants to drop bad while inverted and that's just one more thing to deal with.