On author's trick is this: "Since his novels are written in the first person, the voice is crucial, so he "auditions" narrators by writing a few chapters from different characters' points of view. Before he begins a draft, he compiles folders of notes and flow charts that lay out not just the plot but also more subtle aspects of the narrative, such as a character's emotions or memories."
And then there's this: "When he's in the middle of a novel, Colum McCann sometimes prints out a chapter or two in large font, staples it together like a book, and takes it to Central Park. He finds a quiet bench and pretends he's reading a book by someone else. Other times, when he's re-reading a bit of dialogue or trying to tweak a character's voice, he'll reduce the computer font to eight-point Times New Roman. "It forces me to peer at the words and examine why they're there."
You might find some approaches you could borrow here.
