One changes shades extremely dejectedly, with hesitation (4)
I believe the answer is:
dyer
'one changes shades' is the definition.
(someone who dyes things)
'extremely dejectedly with hesitation' is the wordplay.
'extremely' suggests removing the centre (only the extremes of the word are used).
'with' means one lot of letters go next to another.
'hesitation' becomes 'er' (sound used when hesitating).
'dejectedly' with its centre taken out is 'dy'.
'dy'+'er'='DYER'
(Other definitions for dyer that I've seen before include "Drey (anag.)" , "Cloth worker" , "Changer of colour" , "One colouring cloth" , "Person who colours cloth" .)