It's unwise to hush an artist! (4)
I believe the answer is:
rash
'it's unwise' is the definition.
(thesaurus)
'hush an artist' is the wordplay.
I cannot really see how this works, but
'hush' could be 'sh' (both are used to tell someone to be quiet) and 'sh' is found within the answer.
'an' could be 'a' and 'a' is located in the answer.
A single letter 'r' remains which might be clued in a way I don't understand.
This explanation may well be incorrect...
'to' is the link.
Can you help me to learn more?
(Other definitions for rash that I've seen before include "Lacking in caution" , "Overhasty - skin irritation" , "Impulsive - skin condition" , "Foolhardy with skin ailment" , "Harum-scarum" .)