Reading notes
Keep one useful sentence.
A book does not have to become a large set of highlights to leave something behind.
After a chapter, close the book and ask what deserves to stay with you. It may be an argument, a new question, or a description that changes how you notice an ordinary thing.
Recall before collecting
Write the idea in your own words before reopening the page. A short imperfect summary can reveal more about your understanding than a perfectly copied paragraph.
Then check what you missed. Add the page number if it will help you return later, and keep the note brief enough to read again.
Leave room for a question
Useful notes do not need to sound finished. A question at the end gives the next reading somewhere to begin. Over time, those questions often connect books that seemed unrelated.
Keep the note small enough that you will want to revisit it.