Make small changes to (5)
I believe the answer is:
amend
'make small changes to' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for amend that I've seen before include "Ameliorate" , "Correct error, make minor alteration as to writing" , "Correct or alter to improve" , "Make small improvements to" , "Modify - edit" .)