Like the title says, I'm trying to figure out how I can keep an effective log of the stuff I've done in a project. I'm particularly curious about ways to keep a good project log for a long project (i.e. longer than a month). I've tried to do it, but I have a lot of trouble figuring out exactly what needs to go into the log and what is just rough work and should stay out. I tend to do a lot of rough work, jotting random ideas down, deriving formulas, or trying to help myself visualize something. If I just keep all of that, I end up with an excessive amount of paper, and it's really hard to go through and get anything useful. At the same time, I find myself often wishing I could look back at a little idea I had a while ago for various reasons, and I've been wishing that I was better at keeping records of my thoughts, but I can never seem to figure out at the time what might be important later and what won't be. Does anyone have any tips, or could anyone share their system for keeping records of what they've done or thought of in a project?