The right hand is holding the bullet seating screw in a fixed position so it doesn't rotate, while the left hand grips the die body, and screws it in one eighth of a turn.

Now the most important adjustments are correct for reloading.

Be careful not to rotate the die body or bullet seating screw while setting the lock rings. At this point just take up the threads without tightening, in case further adjustment is necessary. This die has a lock ring on the body, and on the bullet seating screw. Lee dies will have one on the die body only.

Load one round, and check for AOL. If the AOL needs to change adjust the bullet seating screw only, holding the die body in place so it doesn't rotate, till it's correct.

Check the crimp on the loaded round. If you want more crimp, hold the seating screw so it doesn't move, and rotate the die body underneath it in increments of 1/8th turn, till you have the crimp you want. If you end up with an outward bulge below the bullet that has deformed the case, you've crimped too much, reduce the crimp to the point before the deformation was caused.

You should adjust for AOL before you adjust for crimp.

When crimp and OAL are satisfactory, tighten the lock rings without rotating the die body or seating screw. That completes the process.