I found it useful to create a digital check list that can be used to evaluate positions in the backswing and follow through. I also think it is helpful how all the Phases are consistent and build upon one another.
Note: Full swing is similar to Phase III and IV checklist. The difference is the arms, wrists, head and everything should now be neutral - no tension. There is no checklist on finish because everyone is unique at their finished state.
Sample Swing thoughts - pre swing drill
Flat left wrist at impact. Weight shift to left side - joint neutral. Right knee at target. (Phase I) Keep Left arm straight. This promotes full shoulder turn and lag (prevents getting club back or getting club to the ball with elbow flex and not proper turn or lag build up). Shoulders square at impact. Right shoulder dropped lower than the left shoulder. (Phase II) Release club face - square to square to square. (Phase II) Maximum Acceleration on post up - at impact - like throwing a ball. (Phase III) Timing/Tempo - like throwing a ball (Phase IV) Most of my swing thoughts can be practiced in pre-swing drill. Swing thoughts vary over time. Keep reviewing your current checklist items and find which thoughts make a difference.