I've tried a lot of different solutions and none really work for me. In the end, I went back to pencil and paper. Not pen, but pencil. I buy good quality note

I've tried a lot of different solutions and none really work for me. In the end, I went back to pencil and paper. Not pen, but pencil. I buy good quality notebooks like the Midori MD Paper A5, and good quality pencils like the Mars Lumograph. I use the most minimal "system" possible which is a pared-back version of Bullet Journaling with all the dumb stuff removed. Because I can't write nearly as fast as I can type it forces me to paraphrase, and I feel like the cognitive processing therein increases retention. As an added benefit, it's trivial to incorporate diagrams, arrows and stuff to show logical links, etc.