Do these three mobility drills before every squat workout:
Begin by sitting with one leg crossed over the other and the hands supporting the body at the end of the chair. (See photo above.) Lower yourself down to bring the forehead toward the knee. Hold for 5 seconds and repeat for 5 reps on each side.
Begin half-kneeling with the front foot a few inches from the wall. Lean forward to touch the knee to the wall while stretching the opposite hip. Hold for 5 seconds and repeat for 5 reps on each side.
Begin seated or standing against a wall with the arms held overhead. Slide the elbows, wrists, and hands down the wall to the "W" position shown. Hold for 5 seconds and repeat for 10 reps.