This way you can still write and make notes when you are not 'writing.'
How you divide your notes is up to the writer, but this is how I put mine into sections. It was recommended to me years ago and I've kept it up since.
Section 1. Plot ideas.
Section 2. Characters - descriptions, essential information, their past etc
Section 3. Research - how much you do is a person decision and depends on what you are writing about.
Section 4. Plot summaries. I sometimes try to cut and paste the first paragraph of each chapter in here. It helps me focus and make sure the story stays on track.
Section 5 . Questions, about the plot, research I need to do, what would a character need to have done in their past to make sure they are able to survive a forest fire or flood?
The best thing about a good writer's note book is that it makes you feel organised and productive.