I'm working on a plot - I have an excellent outline in my head, as well as a chat log from brainstorming with my friend, and the introduction written out, along with the first chapter outline written. However, I can't work out how to do a dual narrative. My story centralizes around two characters, and their relationship, and I always planned it out as a dual narrative. The problem I'm having, is that I don't want to have it change too often, but at the same time, I know it can't be one chapter one way, one chapter the other. What I'm asking for is, were you to read a novel with two narrators, how would you prefer to read it? Is short and simple okay if it's necessary for the plot? Or is it easier to read if it's long sections? Thank you
Since I just recommended this in another thread: Larry Brown's Dirty Work uses dual narrators to the same purpose, and indeed he does it chapter-by-chapter. The trick, though, is that the chapters are narrated by wildly different voices of two Vietnam veterans from distinctly different backgrounds, and that the chapter lengths are not consistent--only as long as he needs to stay in one person's head, or the other's. You might find it some help, and it's the best example I can think of at the moment.
I don't think you need it to be either short chunks or long chunks throughout the entire book. Have short chunks in some places, and large chunks in other places. It's all about what the scene calls for. You can also change narrator mid-chapter, as long as you make it extremely clear to the reader as soon as you change the POV.
For any given scene, stick to one narrator for the entire scene. There are authors who have been able to ignore this guideline, such as Frank Herbert, but few have been really successful at it.
I'd recommend reading some books that switch between character perspectives and see how they handle it. Off the top of my head I can suggest The Pact and 19 Minutes by Jodi Picoult. Both books actually take on different points of view from a variety of characters. Though until you really master switching between 2 characters I would recommend avoid adding more PoV. Also Legend of Drizzt series makes use of changing character points of view. But just find books that use this and see how they do them. .
Switching only at chapter boundaries is still a good approach. Even many respected, seasoned authors stick to that pattern. Narrator transitions can be tough for the reader to adjust to, so limiting the frequency of switching is prudent.
I'll parrot this and say that the best advice in the thread is to keep your characters separated by chapters, and don't consider word count as the cutoff point for your narrator. Two speakers gives you a lot to maintain in the balance of the story. I'm by no means a great writer, but if I shoot for dual viewpoints I always follow the rule listed above. An additional consideration is making one character the Yin to the Yang, which provides both characters with the ability to poke holes in each others thought processes and consequently creates a more well rounded book. In that vein, it's sometimes fun to rewrite a scene so both narrators explain it, but beware that doing that more than once or twice usually makes readers cringe. "I have to read all of that again?"
You should definitely have a look at the Bartimaeus Trilogy by Jonathan Stroud. In the first book, he switches between two point of views, a human magician, and the demon that the magician summons. In the second and third book, he introduces another character and also tells the story from her POV, as she becomes more and more intertwined within the plot.
I switch around viewpoints in my story. I stay in one character's head as long as that person helps the plot along. When another character is more apt for explaining what is going on then I switch. It is okay to have some short and some long chapters. Leaving the ends with cliffhangers is great. Find some other books which switch around in viewpoints to help you.
All transitions, whether from one narrator to another or from present narrative to a flashback, should be as natural and predictable as possible. Readers are used to and comfortable with narration shifts at chapter boundaries, so, unless you have a strong reason to do it another way, you should stick to that. Or just use third-person omniscient. Decide what's right for your story and stick to it.