Fellow speaker,
Comedian Katie Grady suggests having a list of funny references to use for your humor. Talking about certain things is funny just in talking about them. Jethro from the TV show Beverly Hillbillies, the banjo players from the movie Deliverance, weasels, etc. Make a list of funny references, things that you and others find funny and use that reference list to help out the humor in your speech.
Referentially,
Tim
