Amy Sherman-Palladino's The Marvelous Mrs. Maisel is a tremendously intelligent comedy-drama.
There's a lot to learn from comedy, and even if you're not writing a story that leans heavily on humor or levity, I'd recommend studying comedy anyway. Doing so can drastically improve your dialogue--and maybe even your plot and your character development. Amy Sherman-Palladino is a writer I studied at length when I started taking writing a lot more serious post-college, and her work with The Marvelous Mrs. Maisel is a masterful blend of drama, social consciousness, and character growth. And oh yeah, it's funny as hell--but I wouldn't quite call it just a comedy.
The Marvelous Mrs. Maisel follows a housewife in 1958 New York City who discovers she has a knack for stand-up comedy. The show won two Golden Globes, both in Musical and Comedy categories, but when you watch the first act of the first episode, it's hard to see where the funny lies. The show never gets full-on lol, outside of Miriam "Midge" Maisel's stand-up routines, but even those aren't aggressively peppered with deliberate humor. Her stand-up is dark, contemplative, vulnerable, and real. It's Midge trying to make sense of the abrupt chaos in her life.
When was the last time you saw a bride do stand-up at a wedding? That's the 'unexpected' working.
What is Comedy and how does it work?
Comedy and its origin is, by classical definition, sits across from tragedy. Comedy is a literary genre and a type of dramatic work that is amusing and satirical in its tone, mostly having a cheerful ending. The motif of this dramatic work is triumph over unpleasant circumstance by creating comic effects, resulting in a happy or successful conclusion.
When you take two or more things that don't go together--when their logic and familiarity clash, then you are on your way to making your reader laugh. If they aren't laughing, they are at least questioning the scenario, and are attempting to draw a line that connects the two things together somehow. This is making your reader think about what they're experiencing. The incongruity could possibly have subtext that you're not explicitly stating, arousing intrigue.
Playing on both the expected and the unexpected
What we expect to happen and what we don't expect to happen are two paths with which comedy can explore its humor. It also digs into what is happening thematically with our story, and plays on the main character's arc.
In the beginning of The Marvelous Mrs. Maisel, we see Midge helping her husband Joel with his routine by taking notes. She's analyzing the crowds, their reception of Joel's jokes, and going over the feedback with him. We know that he's struggling and we know he's probably not going to succeed. We don't know that he's stealing the routine from another comedian and we don't know that he's having an affair. And ultimately, we don't know that Midge is going to act out, drunk and heartbroken, by impulsively performing at the comedy club. We don't know that she's going to shine in her performance, but she wins the crowd over after usurping the stage.
What your character wants isn't what they expected
What Midge wants is a question that she will spend the entire show trying to determine, because as a 1950's housewife, she was only ever expected to want to marry and raise a family. Deciding to be a comedian is a "benign violation" of what's expected. It's uncharted territory, much like it was for Midge's real life counterparts Joan Rivers, Mom's Mabley, Totie Fields, and Phyllis Diller. Diller once said "it helps a stand-up to have something wrong."
Your main character has something wrong with them. Without what's happening to Midge, she would never even think to perform stand-up comedy.
Are you taking notes? Don't take too many, because dialogue doesn't need to be rigid and technical.
What makes good dialogue?
Dialogue comes with subtextual purpose
It's not meant to be solely a device that lays out expositional details. Yes, sometimes those details are important, but the less exposition, the better. Instead, consider lines of dialogue as bite sized theme candy. It's easier to convince your reader to eat a whole pack of miniature chocolate Kisses. They're going to be a lot more reluctant to take on a bunch of king sized Kit Kats.
Realistic dialogue is usually really bad
I'm not talking about phonetics, tone or vernacular--which can be essential elements in distinguishing character. I'm talking about what's being said. Many writers, editors and teachers will will tell you to listen to how people talk when learning about dialogue. That's a great exercise, but I'd suggest practicing it with a grain of salt. People in the real world are less inclined to say what they mean. They often aren't in the thick of a conflict in their everyday conversations, which means nothing is at stake and nothing can go wrong, leaving you with dull dialogue to study. Real world dialogue is much more matter-of-factly and less figurative. Does that mean prescribe quick repartee to your dialogue a la Gilmore Girls? No, not if you don't want to. But Palladino's usage of that style is an extension of deploying the unexpected in comedy and humor. What's not being said is often the most important part of dialogue, and it serves as a diversion away from what we expect.
Less is more
Don't you wish I'd write more about this?
Mark Twain once said “The secret source of humor itself is not joy, but sorrow. There is no humor in heaven” (I'm not a Twain fan at all, but the guy made some good points). Humor and contemporary comedy are as much of an exploration of sorrow and pain as any other drama. Humor looks to understand and articulate the unexpected, the uncomfortable, and the painful. That's probably a responsibility of any art that has any sort of message, which seeps through the dialogue.
Just think, what if your main character, right after having her first tragic moment, stumbled upon a stage at a comedy club. What would she say? What wouldn't she say? And how would that impulsive routine change her whole world? Think about that when writing your dialogue. You don't have to explicitly implement it in the dialogue, but have that routine going on in the back of your mind as you're writing.