Show contempt with clues written up (4)
I believe the answer is:
spit
'show contempt' is the definition.
(I've seen this before)
'clues written up' is the wordplay.
'clues' becomes 'tips'.
'written up' says the letters should be written backwards.
'tips' written backwards gives 'SPIT'.
'with' is the link.
(Other definitions for spit that I've seen before include "Roasting spear" , "Skewer on which meat is roasted" , "Expectorate on the tongue of sand" , "on the barbecue?" , "Large skewer-like rod" .)