Tips for hot weather clothing cease to convince (4,4)
I believe the answer is:
wear thin
'cease to convince' is the definition.
(to wear thin is to become unconvincing or tiring)
'tips for hot weather clothing' is the wordplay.
I cannot really understand how this works, but
'hot' could be 'in' (both can mean fashionable) and 'in' is located in the answer.
'clothing' could be 'wear' (synonyms) and 'wear' is found in the answer.
This explanation may well be incorrect...
(Other definitions for wear thin that I've seen before include "Gradually become less persuasive" , "Gradually dwindle" , "Get less convincing" , "Begin to fail" , "Start to fail" .)