Make attractive finale with organ (6)
I believe the answer is:
endear
'make attractive' is the definition.
('endear' can be a synonym of 'make attractive')
'finale with organ' is the wordplay.
'finale' becomes 'end' (I've seen this before).
'with' says to put letters next to each other.
'organ' becomes 'ear' (ear is a kind of organ).
'end'+'ear'='ENDEAR'
(Other definitions for endear that I've seen before include "Draw" , "Make beloved" , "Earned (anag.)" , "ingratiate" , "Cause to like" .)