I can't write it for you, but you might get some inspiration by some of the witty poetry written by Dorothy Parker. Some of my favorites are: Indian Summer, Godspeed, Men, Observation, and Resume.
You can find them at: http://www.poemhunter.com/dorothy-parker/
Then find a rhyming dictionary and thesaurus (my favorite is: http://www.rhymezone.com/) and go for it.
I like to come up with a catchy sentence first that really says what I want to say. Sometimes I might need to tweak it a bit in order to give it a good poetic beat. Then I build the poem around it. I read it out loud a lot as I go to make sure it sounds good.
I love to write poetry, even though it is terrible by any formal standards. I just wrote a poem this Christmas for my son about some of his favorite television shows, and he laughed out loud! That's all the approval I need!
Have fun!
