Recently, I got an opportunity to explore something I'd always wanted to try: improvisational theater. The university where I work has their own troupe, and after a few auditions, I was selected to perform in a show.
Not only has this helped me tap into my creative brain, it's also bred writing opportunities. There's a sketch show along with the improv set in a couple weeks, and I wrote a couple scripts for it. It was tons of fun, and great for honing dialogue.
The more improv I do, the more I realize some of the basic rules (yes, there are rules), tie into writing. Here are a couple I've found that relate:
Don't deny (also known as "yes, and...")
This is probably the most important rule in improv. Both people in the scene need to agree on the premise. If I say, "How about those buscuits?" and the other person says, "Uh, those are scones," then there's nothing really to build from. That's the "yes" part.
The "and" part is even more important. If no one adds anything new, then the people in the scene just stand there. To keep things going, I need to say something like, "Wow, those buscuits must weigh fifty pounds!" and then the other person needs to agree and act like they're carrying really heavy buscuits.
How it relates to writing: This is often referred to as rising action. Once you establish a goal or conflict, you have to add to it--otherwise the plot will fizzle out. Always begin a new conflict before resolving an old one, as long as there aren't too many threads at once.
Don't violate the world (or, the walking through the table rule)
Most of the time, improv doesn't involve props or sets. So if someone establishes that there's a "table" in the middle of the scene, I can't accidentally walk through it. Or, if there's a door, I have to pretend I'm knocking it. Otherwise, the sense of scene is lost, and the audience isn't engaged.
How it relates to writing: When you design fictional worlds, make sure the elements are consistent. Like if warlocks use staffs in one scene, and wands in another, it doesn't work so well. Sometimes I'll write my rules down (particularly if they involve magic). This also goes for established plot lines that may inadvertently get dropped.
Don't try to be funny
This might sound counter-intuitive, but it's true. If someone tries to be funny in improv, it makes it harder for other people to add to what's being built because they aren't a part of the attempted joke.
How it relates to writing: When people try inserting humor into their writing, often it comes off feeling forced. Just let things come organically--if it doesn't feel right, it probably isn't.
Have trust and confidence
Improv is by no means a solitary sport. Everyone in a scene depends on one another--and if there's no trust, it gets tricky. Improvers need to have confidence in others as well as themselves.
How it relates to writing: If I don't trust myself or my abilities, it shows in my writing. All of us struggle with this, I think, at various stages in the process. We just need to listen to our instincts and do what's true for us. Whatever that might be.
For fun, here is an excellent example of improv done right (courtesy of Whose Line is it Anyway?):