In his book "What We Laugh At... And Why," comedian and storyteller Stevie Ray talks about the three basic elements of humor writing that make us laugh. To get a giggle, humor must be either unexpected, recognizable or at someone's expense.
Unexpected humor is humor that comes as a surprise to the reader. It might be a non sequitur, or an action or behavior that doesn't fit with the character's personality. Recognizable humor happens whenever you laugh at a story and say to yourself, "I know exactly what they mean!" Humor at another's expense can be tricky. The best example of this kind of humor is satire directed at a group of people in power, like a government or cultural majority. When humor is at the expense of a minority or an individual, it often comes across as bullying --- and that's not funny.
Conflict is one of the most important aspects of good creative writing in general, but it's especially important in a humorous short story. "Take the conflict out, and you have no story," says writer Shevi Arnold. Without conflict between characters (or internal conflict in one character), a funny story becomes little more than an extended punchline.
Shakespeare once said, "Brevity is the soul of wit." A funny short story should be just that --- short and to the point. Many novice story writers make the mistake of starting the story before it gets interesting and dragging it out far longer than it needs to be. The funniest stories aren't padded with a lot of unnecessary details about how the characters ended up in a certain situation. Instead, the author drops them directly into the middle of it. This technique is known as "in medias res," which literally translates to "in the middle of things."
The element of comedic distance can mean the difference between a sad short story and a hilarious one. Actress Carol Burnett once said, "Comedy is tragedy plus time." Short story writer David Sedaris utilizes comedic distance when he writes about his awkward and often traumatizing childhood. If he had attempted to write many of his stories at the time they occurred, they most likely would have come out quite tragic. With time, however, Sedaris is able to transform those moments into nuggets of comedic gold.