Get A Notebook And Write Stuff Down

Greg Morris writing about notebooks:

You don’t need to start a second brain, or do some weird PKM stuff, you just need to have a place full of things that will help you out. Record things you find interesting, things you need to remember, things that might help you work later on, literally anything you might need later on. You don’t need to start a commonplace book or anything, you just require a notebook around, all the time.

I start to wonder if there is a more straightforward way to manage ideas other than keeping a full PKM or Zettelkasten.