To write a good limerick, the first rule is to understand the specific rhyme scheme and the specific meter.
Rule No. 1. A limerick has five lines.
Rule No. 2. The first two lines rhyme with each other, and with the fifth line. The third and fourth lines rhyme with each other. Think A-A-B-B-A. If the last word of your first line is difficult to rhyme (examples might be Pelosi, Limbaugh or Microsoft), then recast it.
Rule No. 3. The meter is specific. Do not try to break this rule or your limerick will fall flatter than a cake in a cold oven, in which case do not enter it in the contest.
Line 1 and Line 2 are the same: da DUM da da DUM da da DUM. (Notice there are 3 DUMS or beats.)
Line 2: da DUM da da DUM da da DUM. (Example: There once was a banker named Thain…)
Line 3 and Line 4 are the same: da DUM da da DUM (notice there are 2 DUMS or beats. Example: Thain bought a nice rug…).
Line 5: Reverts to the meter of the first two lines.
Rule No. 4. Cleverness counts. If you can figure out a good rhyme for Limbaugh or Pelosi, and it fits in the required meter scheme, then you get points for difficulty. It's OK to make up words, but again, only if they're clever.
A tip: If you must, you may add a small “da” at the end of Line 1, like this: “da DUM da da DUM da da DUM da.” (There once was a Speaker named Nancy…). If you do, you must add it to lines 2 and 5 as well. (Whose wardrobe was always quite fancy….)
Or you may add an extra “da” in lines 1,2, and 5. da da DUM da da DUM da da DUM.
One final tip: Save your best, cleverest rhyme for the final word. End with a bang.
More about writing limericks: