He's concerned with his image, being badly tailored (8)
I believe the answer is:
idolater
'he's concerned with his image' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'badly tailored' is the wordplay.
'badly' is an anagram indicator.
'tailored' anagrammed gives 'IDOLATER'.
'being' is the link.
Can you help me to learn more?
(Other definitions for idolater that I've seen before include "I put off" , "Person who worships graven images" , "Tailored for image worshipper" , "No orthodox believer" , "I'm devoted to my image" .)