I am learning rolling loops as well and the best method for me is to start slow. Like rolling circles, I am starting with only one roll. Much like pattern flying. Gradually I will increase the rolls as the plane comes around to make a loop. I can profeciently do rolling circles left and righ from any attitude. I even close my eyes for a couple of seconds just to see that I know where the plane will be as I imagine it with eyes closed. It really gets you in tune with the brain to fingers coordination. It is hard to do with a strong wind though as it is hard to tell the amount of force the wind will push the plane. Still fun to do though.
PS dont do it at 5' high
Adam