Observe you accept the money (4,4)
I believe the answer is:
take note
'observe' is the definition.
(I've seen this in another clue)
'accept the money' is the wordplay.
'accept' becomes 'take' (to accept is to take possession of).
'the money' becomes 'note' (I am not sure about this - if you are sure you should believe this answer much more).
'take'+'note'='TAKE NOTE'
'you' acts as a link.
Can you help me to learn more?
(Other definitions for take note that I've seen before include "what the stenographer does" , "mark?" , "Observe closely" , "Pay attention" , "Observe and absorb - jot it down" .)