Noble actor is about to get into painting (10)
I believe the answer is:
aristocrat
'noble' is the definition.
(thesaurus)
'actor is about to get into painting' is the wordplay.
'about' indicates an anagram.
'to get into' indicates putting letters inside.
'painting' becomes 'art' (I've seen this before).
'actor'+'is'='actoris'
'actoris' anagrammed gives 'istocra'.
'istocra' put within 'art' is 'ARISTOCRAT'.
(Other definitions for aristocrat that I've seen before include "Patrician" , "Noble" , "toff" , "Member of the nobility" , "Nob" .)