Form is essential with this squat. The bench squat helps you with finding and fine tuning your form, when done correctly. Engage your core, roll your shoulder blades back and down (check video for bar placement, not too high, not too low, meaty part of the shoulders). Ensure your back is straight (weight belt will help with this), do not hunch forward on descent or in the lift. When descending, push your rock hard glutes out while supporting the weight on your thighs. Do not bow forward, that is how you f@ck up your back.