Think and focus on your feet and heels when you roll one time. Note if they are both planted in the earth and than are moved off it by the power of your body movement. Work on adding the movement and relaxation of the heels and feet in rolling by first leaning forward by relaxation and starting the change of contact with the earth from feet to body by the movement of the heels and feet. Remember you have two feet and two hips so you can move one of them or both to start the roll. For example lean forward and lift one heel off the ground and turn it outside of your body. Relax the body and let it move to align itself with the heel and with the toes move your body and relax the other heel to let the roll happen rather than throwing yourself off your feet and feeling fear and lack of decision while you fight yourself. Keep breathing.