You will fill in the left-hand strip and make the page testable.
This is the step almost everybody skips, and it is the one that makes the difference. After class — the same day, while it is still fresh — go down your notes and write a question in the left strip for each chunk.
The same notes, with questions added afterwards.
A good question is one you cannot answer by looking at the shape of the page. "What goes in?" makes you produce three things from memory. "Photosynthesis" makes you produce nothing — it is a label, not a question.
Take each heading and put what, why, how or what happens if in front of it.
One question per chunk of notes, not per line.
If you cannot think of a question for a chunk, that is useful information: you did not understand that bit. Mark it and ask.
Now the page is a quiz. Fold it, or lay a sheet of paper over the right-hand side, and answer your own questions out loud. That is revision — reading the page over and over is not.
Which of these is a good question for the left-hand strip?