Directs fair centre writing (4)
I believe the answer is:
aims
'directs' is the definition.
('aim' can be a synonym of 'direct')
'fair centre writing' is the wordplay.
'centre' says to take the centre.
'writing' becomes 'ms' (abbreviation for manuscript).
The middle of 'fair' is 'ai'.
'ai'+'ms'='AIMS'
(Other definitions for aims that I've seen before include "objects" , "Sets sight on, having ambitions" , "Targets and ambitions" , "Objectives; points" , "Proposes or intends" .)