Sly person doesn't start to stand (5)
I believe the answer is:
easel
'stand' is the definition.
(stand for an artist's canvas)
'sly person doesn't start' is the wordplay.
'sly person' becomes 'weasel' (I've seen this before).
'doesn't start' means to remove the first letter.
'weasel' with its first letter taken away is 'EASEL'.
'to' acts as a link.
(Other definitions for easel that I've seen before include "stand supporting artistic effort" , "Constable's supporter" , "Blackboard-frame" , "artistic aid" , "Artist's prop" .)