How to amuse motorists? Hardly! (6)
I believe the answer is:
divert
I'm afraid I can't explain this answer.
Can you help me to learn more?
(Other definitions for divert that I've seen before include "Entertain; reroute" , "Deflect - amuse" , "Capture attention of" , "Amuse or send another way" , "Turn something from its normal course" .)