Even when I’m drafting, I often think about other books I have in the pipeline that are not the current work-in-progress. I used to have a rule that I was allowed to write whatever I wanted on any project, as long as I only used a pen and paper on things that were not my main focus project. That way I could jot down scenes and dialogue and ideas all I wanted, but I wouldn’t risk project hopping.
These days, I type everything, but in my days of paper freewrites I developed a rhythm that’s still useful to me. I might open a file and write down a scene, but once I’m done emptying my head of the ideas, I’ll stop writing, not pushing myself to do more like I will on the project I’m focusing on. I’m allowed to do that as often as I like, but I don’t skip out on the project I’m supposed to be doing to write long sections of other books, because I don’t want to get distracted by shiny projects when I should be doing other things.
Still, I love freewriting. I get to write whatever I want, no matter how stupid it is. I get to write scenes exactly how I picture them, without having to fit them into the plot. The parts of the book that I daydream about are almost always the climactic relationship scenes: moments of conflict or resolution or fulfillment between two characters where for both parties, the stakes are high. I almost never include setting or much action; I always write long, long strings of dialogue. Writing these scenes helps me to figure out how my character will react to conflict and pressure, and how struggles between her and other big players in the book might go. These scenes are always heavily re-written if they make it into the book, but getting the ideas down helps me to figure out what I want the character arc to look like.
Those are my rules for pre-writing: write it down and put it down, don’t project jump, write whatever I want, explore the relationships. This is one of my favorite parts of writing, so I try to enjoy it.