1. You have horrible taste in music.
2. Where do I get some of those shorts?
3. The squat looks pretty good, except for a tendency to go to your toes/let your knees slide forward at the bottom. Shove your butt back and your knees out as you hit the bottom.
4. Learn to squat without that object under your ass as a depth gauge. If your mechanics are correct, your depth will be too. Once you learn depth, it should not need reinforcing every rep.