Bad way to apply? (3)
I believe the answer is:
dab
'apply?' is the definition.
(I know that dab is a more specific form of the action apply)
'bad way' is the wordplay.
'way' indicates an anagram (another way of arranging the letters).
'bad' is an anagram of 'DAB'.
'to' is the link.
(Other definitions for dab that I've seen before include "A bad, backward fish" , "Apply small amounts (usually a liquid) to a surface" , "Bad kind of fish" , "Expert; flat fish" , "Flatfish; fingerprint" .)