When a writer tackles a book on a part-time basis, it can be a slog to keep the flow of the story smooth across umpteen chapters. Too much time and life happens in between writing sessions.
To better keep chapters flowing naturally, ending with proper hooks, progressing to more urgent action, etc., I use a timeline. Across a loooong sheet of paper, I horizontally tabulate each numbered chapter and what happens in it. This way, I can refresh my memory about the last time two characters crossed paths, or the circumstances on which they parted.
I keep the descriptions brief and sometimes change them as I edit or change the events in the chapter. Sometimes whole chapters get moved around, too. No law says you can’t.
And on one day, a plot device may seem divine. On a different day, it may make you hoot at whatever the heck you were thinking. Or you realize you’ve sprung a plot device too soon and need to move it back a bit. Plent of flexibility here.
You won’t lose the plot by using a timeline.