Write a play.
Playwriting is a shitty career but an excellent teacher. Start with a one-act. You’ll have roughly 30 minutes to take your audience on a simple journey. You’ll need to bring characters to life using nothing but their observed behavior. (Dialog is behavior. Interesting characters rarely say what they mean. Unforgettable characters lie—especially to themselves) It’s the very definition of showing and not telling.
You’ll have to convey exposition instead of dumping it. You’ll have to construct your plot from your characters’ needs and wants and show them interacting with each other to pursue those needs and wants. The plot will have to be interesting, surprising, and in the end inevitable. Any humor will need to come from who you’ve shown your characters to be.
You’ll have to do all this without fancy prose, outside scenes and elaborate character descriptions. (Don’t waste your time writing a paragraph to tell the actor who their character’s supposed to be. The good ones will cross it out. They can’t portray description. The character is who their behavior reveals them to be.)
Once you’ve written your script, get the best people you can to read it out loud. If there’s a community theatre close by, ask if you can stage a reading. Offer the actors a small stipend. Invite your friends to be the audience. You’ll learn more in one afternoon than from a year of classes.
Hearing your words coming out of someone else’s mouth is a trip. It’s also humbling. Listen with your whole body. Observe your audience. What makes them lean forward in their seats. What makes them laugh. Is it a good laugh? Or are they laughing at something incongruous that distracts from your story? Where do they tune out? Do they gasp or otherwise react with surprise? (The best feeling in the world! Well, one of them…)
Afterwards, ask the actors what worked for them and what didn’t. Listen humbly. DON’T TALK BACK. Your feelings may be hurt, and the comments may seem wrongheaded and frankly, stupid. But don’t defend yourself or your writing. (Have a legal pad and take notes. If you need to, write things like “What a dumb comment.” Anything to keep from shutting down the actors by telling them how they should be viewing your precious work.) Remember, the actors don’t have the big picture like you do. Their value is their singular focus on their character.
Later on, when you’re alone, analyze their comments. Look for the diagnoses but not the suggested treatments. (People love to tell you what you need to do. Ignore that part and focus on what problem their suggestions are trying to solve.)
See if you can identify patterns in the comments. (If one person has a particular issue, that’s less telling than if many people do.) Do your characters state their motivations too bluntly? Does the plot require them to act inconsistently? Is the dialog too generic? Is it too formal? Do all the characters sound alike? Make notes and prepare to rewrite.
Start by tightening the story. Strip each line down to its essentials. Get rid of every “okay,” “well,” “in my opinion,” and other elements of daily speech that clutter the dialog. Eliminate cliches. Next, add in any missing beats. Revise confusing moments. Find ways to address the issues identified by your actors.
Stage another reading. Get different actors if you can. Feel proud when things that were broken before actually work now. Feel humble when it still doesn’t have the impact you were looking for.
It’s an extremely challenging process. You’ll probably fail at it. But you’ll learn so much in the process. The next time you sit down to write fiction, you’ll find yourself naturally stripping it down to its essentials. You’ll reveal your characters through their behavior. Your dialog will be crisp and interesting.
In short, you’ll be a better writer.