Note: These are my strategies based on reading Judy's book, not what she actually wrote, so if these don't give you the outcomes you want, mea culpa, don't blame Judy.
Strategy 1: The Mind Map
When you notice that something is funny, write down the topic AS A NOUN PHRASE. Write it in a bubble in the center of a piece of paper. Now ask "What's wierd about (topic)?" Draw your answer in a little bubble and connect the two bubbles with a line. Keep asking "What's wierd about (topic)?" until you run out, drawing lines out from the center. Then ask "What's stupid about (topic)?" until you run out. Then ask "What's hard about (topic)?" until you run out. Then ask "What's scary about (topic)?" until you run out.
Most of this will be hack, because anyone who went to college can take it this far. The useful stuff comes when you take it out another level, when you ask what's wierd, stupid, hard and scary about everything you just wrote. Then you have a rational description of the irony of the topic as you understand it. Only the rational can be foolish. This technique works even better with a comedy buddy (see below), because they can make you prove or defend your responses. Rational and complete. Rational is not logical; it's just the product of sincere, exhastive thought.
Strategy 2: The Comedy Buddy
Pick another comic. Make an appointment to meet somewhere free of the distractions of other people you know. Be on time. Ask how long you want to go, and give half of the time to Comic 1 to pitch ideas. Comic 2 helps Comic 1 go through the mind map and requires Comic 1 to convince him/her that their answers are complete and rational. When you finish a Mind Map, work together to turn it into a joke, and look for mixups of two irrational concepts and act-outs of characters in the joke. Switch at halftime.