On The Grid
Tutting drills for the combination's box section. Think of dancing on a grid, like graphing paper.
Flexed hands are right angles, never curved. Every line is super straight. Work with as much tension as you can, squeezing the arms and hands so the shapes lock in.
It loops, so drill it as long as you like, left side then right. A mirror helps at first. Shake out and stretch your wrists afterward.