Guidance for deputy after promotion (6)
I believe the answer is:
advice
'guidance' is the definition.
(I've seen this before)
'deputy after promotion' is the wordplay.
'deputy' becomes 'vice' (as in vice-president).
'after' says to put letters next to each other.
'promotion' becomes 'ad' (short for advert).
'vice' put after 'ad' is 'ADVICE'.
'for' acts as a link.
(Other definitions for advice that I've seen before include "What lawyer offers" , "Counsel given" , "Warning - guidance" , "Suggestion for appropriate course of action" , "Guidance; delivery note" .)