Practice 4 point rolls first, then move on to slow (and I mean slow) rolls. This will give you the basic stick movements.

Once you have this mastered, practice them on 90 degree lines (directly away and directly toward you).

My rolling circle is basically several slow rolls strung together with a touch of elevator and rudder in each of the four points to scribe the circle. I spent a fair bit of sim time to train the motor response....