With a mop handle practice:
Back Squat with 3 pauses–1/2 way down, at the bottom, 1/2 way up, stand
Front Squats with 1 1/4 pause–go all the way down and 1/4 back up,
pause then go all the way down again and back up completely.
Do each of these as many times as you need to cement that correct
position in each of the pauses. This is about perfection in the
positions. Don’t do them sloppy and think that counts as anything!