My apologies for not posting sooner, but personal life has gotten in the way of many things, so if you were eagerly awaiting another component of good humor, thanks for your patience.
Another important component of humor is Exaggeration. Mel Helitzer, author of Comedy Writing Secrets, discusses the Rule of THREES of humor. This is the second E (I'm working my way backward through the list).
Basically, things that are ordinary are not always funny. Most jokes involve some type of exaggeration and/or absurd to make the humor. For example, there's the joke about the three guys who are all going to be executed by firing squad. The first man is lined up, the shooters take aim, and he yells "TORNADO!" Everyone runs for shelter, and he runs off safely. The second man is then lined up, the shooters take aim, and he yells "HURRICANE!" Everyone runs for shelter again, and the man runs off to safety. So the third man is lined up, the shooters take aim, and the man yells "FIRE!"
Now, we all know that 1) three men are not going to be executed by firing squad in sequential order, 2) They're not going to be able to trick a bunch of executioners, especially twice in a row, and 3) the last guy is not going to be so dumb as to yell out a disaster that just so happens to be the command to pull the trigger. But by exaggerating that idea, we're able to create the humor in the joke.
(NOTE: If you pay careful attention to the previous lesson on Surprise, you'll also see that the joke followed that formula: We would expect the third man to yell "BLIZZARD" or "LANDSLIDE." Instead he yells the one thing that doesn't work at all.)
Here's one of my own examples I've been using during some of my speeches: We're potty training my three-year-old son by using a digital kitchen timer. Every 60 minutes it goes off and he runs to the bathroom, ready to go. The problem now, however, is that he wets his pants anytime a truck backs up.
So remember, a great way to create a joke in a speech or presentation is to EXAGGERATE the punchline. Don't make it out of the ordinary, make it extraordinary, and you'll get the laughs.