Wearing fashion to shop (6)
I believe the answer is:
inform
'shop' is the definition.
(to shop someone is to inform the police about them)
'wearing fashion' is the wordplay.
'wearing' becomes 'in' (wear in (and 'in' is fashionable)).
'fashion' becomes 'form' (both can mean to shape something for a purpose).
'in'+'form'='INFORM'
'to' is the link.
(Other definitions for inform that I've seen before include "effective" , "Provide facts - playing well" , "Spill the beans" , "Certify" , "'Apprise, notify (6)'" .)