What should a first responder or passerby do regarding a fallen motorcyclist's helmet at a crash scene?

1. Do NOT remove the helmet unless the rider is not breathing or their airway is blocked, to avoid worsening potential spinal cord fractures
2. Remove the helmet at once so the rider can breathe more easily
3. Remove the helmet to check for head injuries before help arrives
4. Sit the rider upright and take the helmet off to keep them conscious