Put on party before November (3)
I believe the answer is:
don
'put on' is the definition.
(as in donning or putting on an item of clothing)
'party before november' is the wordplay.
'party' becomes 'do' (do can informally mean a party).
'before' says to put letters next to each other.
'november' becomes 'N' (phonetic alphabet: alpha, bravo, charlie etc.).
'do'+'n'='DON'
(Other definitions for don that I've seen before include "Yorkshire river" , "Flower" , "and 13 Down: Mozart opera" , "Put on clothes like noss" , "University teacher" .)