How a golf lover can show humility (6)
I believe the answer is:
grovel
'show humility' is the definition.
'how a golf lover' is the wordplay.
'how' indicates an anagram (I've seen this in other clues).
'a golf' becomes 'g' (phonetic alphabet: alpha, bravo, charlie etc.).
'g'+'lover'='glover'
'glover' anagrammed gives 'GROVEL'.
'can' is the link.
(Other definitions for grovel that I've seen before include "Behave obsequiously in fear or servitude" , "Creep" , "Prostrate oneself" , "Cringe, be obsequious" , "Cower, abase oneself" .)