Out of the hole your hips rise faster than your shoulders, turning the squat into a good morning and dumping load onto your lower back.
Cue "chest up and back into the bar"
Drive your upper back into the bar as you stand rather than thinking about your hips.
Add pause squats at two to three seconds
This kills the bounce and forces the quads to do their share out of the bottom.
Front squat regularly
The position punishes any forward lean immediately, so it teaches the pattern faster than cueing.
Check your bar position is consistent rep to rep
A bar that creeps up or down changes the whole lever arm.
The hardest part of fixing a form fault is that you cannot see yourself lift. Upload a video of your back squat and CleanerReps returns specific written corrections against a checklist built for that exact lift, usually in a couple of minutes.
Check your back squat formTwo free analyses, no card required. $19/month after that.