This made me take a step back and rethink how I was teaching the overhead squat. I realized a few key things always seemed to go wrong; shoulder position, squat depth, and bar placement. This is how the Bottom Up Overhead Squat came around.
First and foremost, work on your squat mobility. The biggest inhibitor to the overhead squat is squat range of motion, mainly in ankles and hips. The overhead squat is like an amplifier. Any problem you have in your normal squat will be ten times worse in the overhead squat.
The idea is simple. Allow athletes to sit in the bottom of a squat and find an externally rotated and active shoulder position at the top and bottom of the overhead squat.
The steps are also simple. Find a dowel or PVC pipe and squat on a medicine ball or something of similar height. Hold the dowel in a wide ‘snatch’ width grip. Twist your arms into the dowel, forcing external rotation and bringing it overhead. Make sure your arms are in the proper position. Once set, drive your heels into the ground and stand, trying to keep your chest upright. If you are unable to do this well the first few times, keep working at it. You may even want to set yourself up in front of a wall, forcing an upright torso.
When you first try this, do it with a dowel or PVC pipe. Use something light. As you become more confident, you may want to try this with a 15kg or 20kg bar. This is a great drill to work on once or twice a week. It will help you in your path to a solid overhead squat.