Before learning to correctly take notes, I used to not get much value from reading books. I had read non-fiction for several hours a day, but it wasn’t really useful for me. My approach was not pragmatic. After reading “Take Smart Notes”, I didn’t forget a single thing I found important in a book. It teaches you how to do properly take notes and consume content.
Besides reading that book, I’d recommend seeing how people organize they knowledge using modern tools.