Plan quietly to crush man with salty wife (4)
I believe the answer is:
plot
'plan quietly' is the definition.
'plot' can be an answer for 'plan' (plotting is a kind of planning). I am unsure of the 'quietly' bit.
'crush man with salty wife' is the wordplay.
'crush' becomes 'p' (I can't explain this - if you can you should give a lot more credence to this answer).
'man with salty wife' becomes 'lot' (I've seen this before).
'p'+'lot'='PLOT'
'to' is the link.
Can you help me to learn more?
(Other definitions for plot that I've seen before include "Conspiracy, secret plan" , "Machination" , "Chart - area" , "Patch of ground" , "Story or piece of land" .)