As someone who completed long and detailed personal projects, and someone who has worked on others not to completion, and is working on one now, my advice to myself and to anybody else who is like this is to, at least once per day, just open the thing.
Maybe it's your notes for your novel, maybe it's your timeline in DaVinci Resolve or Sony Vegas. Maybe it's the tracker for your audio. But whatever it is, without even committing to doing any work at all, just open it up and take a look. Every day.
You absolutely do not need to put in work on the thing every day. Do not commit to that. Just open it.
