Colour given by me to painting (12)
I believe the answer is:
pigmentation
'colour' is the definition.
(pigmentation is a kind of colour)
'by me to painting' is the wordplay.
'me to painting' can be anagrammed to 'PIGMENTATION'.
Though, I am not clear how this is indicated.
'given' acts as a link.
Can you help me to learn more?
(Other definitions for pigmentation that I've seen before include "For example, madder" , "Natural colouring" .)