Pay attention, observe (4,4)
I believe the answer is:
take note
I believe this clue is a double definition.
'pay attention' is the first definition.
(I've seen this in another clue)
'observe' is the second definition.
(I know that observe can be written as take note)
(Other definitions for take note that I've seen before include "Observe and absorb - jot it down" , "Observe closely" , "what the stenographer does" , "Pay attention" , "mark?" .)