Stop making a boy sit awkwardly (6)
I believe the answer is:
desist
'stop' is the definition.
(desist means to stop)
'a boy sit awkwardly' is the wordplay.
'a boy' becomes 'des' (short for Desmond).
'awkwardly' indicates anagramming the letters.
'sit' with letters rearranged gives 'ist'.
'des'+'ist'='DESIST'
'making' is the link.
(Other definitions for desist that I've seen before include "Stop, discontinue" , "Stop, whoa, give over" , "'Give over, refrain (6)'" , "Eject; annoyed" , "Cease; abstain" .)