*Find a new 1 rep max today! Rest 2-3 minutes between sets.
Pick loads that allow you to attempt to set a PR in the later sets. If you are not comfortable performing very heavy back squats, add a few reps to each set and drill your mechanics, but try to expose yourself to a load that is relatively heavy for you.
Back squat 3-3-3-2-2-1-1-1 reps