Sent up writer's papers covering gallery (8)
I believe the answer is:
imitated
'sent up' is the definition.
(to send up can mean doing an impression of)
'writer's papers covering gallery' is the wordplay.
'writer's' becomes 'im' ('writer's' could mean 'the crossword setter is').
'papers' becomes 'id' (identification papers).
'covering' means one lot of letters goes inside another.
'gallery' becomes 'tate' (I've seen this before).
'id' going around 'tate' is 'itated'.
'im'+'itated'='IMITATED'
(Other definitions for imitated that I've seen before include "Took off" , "Copied the behaviour or mannerisms of" , "Copied, simulated" , "Followed" , "Aped, copied" .)