If you're not sure what backstory is, it's quite simple: Backstory is what happened to your characters before page one. (Authors may also write backstories that are not intended to be included in their book, to give their characters more depth and reality, just as some actors write backstories for their onstage characters, but I'm not talking about that kind of backstory here.)
Exposition or expository writing is the vehicle for revealing a book's backstory to readers; handled well, it can be brilliant. But most beginning writers use it like a shoehorn, shoving ten pounds of information into a two-pound line of dialogue.
This "shoehorning" and "info-dumping" most often occurs early in a book, and is the reason that I could probably eliminate—unseen—every first chapter from every first draft on the planet, with no significant loss to global literature.
Often these clunky lines of expository dialogue begin with "Remember when I/we...?" Unless the person being addressed has dementia, they probably remember when that happened, or the charcater wouldn't be asking. So, make the memory brief and conversational, like having a well-to-do person say "Time to bang the radiator, darling," to their spouse as they turn up the central heating. Don't succumb to the urge to get all detailed/tedious, like "Remember back when we had our old walk-up on East Fourth and we'd always have to bang on the radiator to get any heat?" If the colorful anecdote is crucial to the backstory, then have the character reveal it in thoughts, or at least have them tell the story to someone who wasn't there, sharing the experience.
Dialogue isn't always the only offender when it comes to exposition. I so often see writers "dump" expository info in their descriptive text—which always makes the book feel like an old-fashioned romance novel—as well as funneling way too much backstory into their character's everyday thoughts and memories.
Remember that, in the early chapters, we readers only need enough info/backstory to get to the next chapter, not to the end of the book. Portion information out slowly, like it was war-time rationing—don't use up all the butter on day one. Make us wonder, make us curious, and you'll make us want to keep reading!
Below are a couple tips for those wanting to self-edit their first (or twenty-first) draft prior to sending it to their writer's group, beta readers, or an editor. I suggest getting feedback, rewriting, and self-editing your manuscript before spending time and money on an editor, and all of this should happen before showing it to a prospective agent or publisher, or god forbid, publishing it.
- Look for lines of dialogue that begin with "Remember...?" Others to look for are "That's just like when I/we once..."
- Edit early dialogue down to its essence, so that lines contain only the most crucial info.
- Be ruthless about cutting adjectives, especially when describing your main characters. it's enough to know that a character is in her thirties, red-haired and curvy. It's not necessary, on page one, to know that she is "green-eyed, auburn-haired, voluptuous, statuesque, and sensuous." Less truly is more.
- Beware of people looking in mirrors and summing themselves up. See above.
- Beware of set ups that involve someone summarizing the past to another person or group. This often happens with characters in positions of authority, like parents, teachers, judges and heads of companies. Look for lines that begin "You may not know what happened back then..."
I'll be teaching a new workshop on this very subject, called "Backstory: Employing Expository Like a Screenwriter" at this fall's SCWC (September 25-27, Irvine, CA). Hope you can attend; it's going to be a great conference.