Strive to cheat as many as possible (2,3,3,3)
I believe the answer is:
do all one can
'strive' is the definition.
I don't know anything about this answer so I can't tell whether this works.
'cheat as many as possible' is the wordplay.
I cannot really understand how this works, but
'cheat' could be 'do' and 'do' is found within the answer.
'many' could be 'l' and 'l' is found in the answer.
'possible' could be 'on' ('not on' can mean unacceptable or not possible) and 'on' is found within the answer.
This may be the basis of the clue (or it may be nonsense).
'to' acts as a link.
Can you help me to learn more?
(Another definition for do all one can that I've seen is " Try one's hardest".)