The memory aid I used was 4 engine, 4 congifuration, 2 weight, 2 pilot input...

4 engine:
- Critical engine inop
- Prop on critical engine windmilling (unless autofeather installed)
- Takeoff or max avail. power
- Sea Level

4 Configuration
- Gear up
- Flaps in T/O position
- Cowl flaps in T/O position
- Max sea level gross weight

2 Weight
- Max sea level gross weight
- Most unfavorable CG (usually aft)

2 Pilot Input
- Airplane airborne and ground effect negligible
- Up to 5 degrees of bank towards operative engine

Other members explain how these change Vcm, but this memory aid helped me. Good luck.