Go: Keeping your feet flat on the floor, squat down so the ball rolls up your back, until your quads are just past parallel to the floor. Hold for a count, then lift just your toes into the air to push through your heels as you rise back to the starting position, rotating your glutes and hams inward. Lower your toes back to the floor before starting the next rep.
Note that this recommendation is for total weekly volume, which means it would need to be divided up based on how many times you’re training each muscle group per week. So, for example, someone training everything twice per week would do 30-70 reps for each bigger muscle group in each of those workouts, and 15-35 reps for each smaller muscle group in each of those workouts.