I do 24-hour comics as close to the original concept as I possibly can: I don't plan out what the story will be beforehand, write anything, or design characters. Partly this is to stick to the rules; partly it's to keep me (and others) from having high expectations for the story.
At the starting bell, I draw a Pictionary card from the box and use the five words that are on it to launch the story. Sometimes I do know what kind of story I want to tell, (this year I wanted to do a space adventure story) and that does help focus my efforts, but I never think about characters or plot until I draw that card.
This year's comic was pretty grueling compared to previous years, in that I had no idea where the story was going from page to page. I was almost halfway through before I had any ideas of how to conclude it, and so I was not that amped about the story anyway. Reading it now, it's not that bad. Kind of funny. Pretty random.
The Pictionary Card words were:
Caterpillar
Box
Sapphire
Victory
Yodel
Caterpillar
Box
Sapphire
Victory
Yodel
Enjoy! Click on image below to start the madness: