I write my stories chapter by chapter, without a detailed outline. I know what I want the story to be about. I like the spontaneous development of the action and the plot instead of a carefully scripted outline in advance.
Anne Lamott writes about this in her book, Bird by Bird. Ms. Lamott writes with great humor. I recommend Bird by Bird for aspiring writers.
Including humor into a novel, which has serious intent, makes the story believable. My friends use the phrase, “you can’t make that stuff up.” That phrase alludes to the humor that exists in many difficult human interactions.
Humor is just one of the suggestions from Ms. Lamott's book . Persistence is another.
Creating a novel length story requires the persistent application of a daily writing regime. When the scope of my story seems overwhelming, when the plot and characters seem too complicated for me to grasp, I just write, I write my way through one difficult scene or chapter, then see where it leads.
I do my writing “Bird by Bird.” You can find out what that means in Ms. Lamott’s book. I found a used copy on Amazon. Highly recommended.