Impromptu is one.
It means "Not prepared in advance; impromptu: an off-the-cuff remark".
Punch, hit, whack, beat, thwack, strike, sock, clobber
Adlib means to improvise. It is often used in the context of a made up on-the-spot performance. Some synonyms include impromptu, unplanned, and off-the-cuff.
how to turn down the voice the ozeri cuff
The cast of Two Off the Cuff - 1969 includes: Ronnie Barker Deryck Guyler
unplanned off-the-cuff impromptu
Off the cuff?
Embark
finishing off
takes off
off-the-cuff guess: Seth.
lay off, discontinue