The gymnast should watch their toes the entire time to help keep their head in and body hollow. Repetitive back extension rolls to just short of handstand. A back extension roll should be performed with the head in, looking at the toes. It should stop just short of handstand and roll forward, to a crouch, then repeat. The initiation portion of this skill is important.
Most gymnasts tend to lean forward or reach for the ground as they go into the roll.
The hands should be kept up and the torso should be vertical. The gymnast should sit back bending their knees slightly, and shortly before their bottom contacts the ground aggressively push backwards for momentum. From here the legs should be kept straight and directed towards the ceiling.