Make sure everyone who flies your aircraft is taught to do the following, just prior to start:
- Throttle closed
- Igniters on / Mixture rich (depending on type)
- Rotor Brake off
- Blades athwartships / tiedowns off (type dependent again)
The menmonic BITT (Brake, Igniters, Throttle/Tiedowns) may also be of use.
Takes 15 seconds but saves a lot of grief.