Do wrong, offering paste, pocketing diamonds (5)
I believe the answer is:
misdo
'do wrong' is the definition.
'paste pocketing diamonds' is the wordplay.
'paste' becomes 'miso' (I've seen this before).
'pocketing' means one lot of letters goes inside another.
'diamonds' becomes 'd' (abbreviation in bridge say).
'miso' going around 'd' is 'MISDO'.
'offering' acts as a link.
(Other definitions for misdo that I've seen before include "Perform improperly" , "Perform wrongly" .)