Get just right (4)
I believe the answer is:
nail
'get just right' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for nail that I've seen before include "one wouldn't want in one's coffin?" , "Arrest (informal) - fix" , "Spike, fasten" , "What one has at one's fingertips" , "It needs a hammer (or a file?)" .)