Explain To Others
By pre-reading, reading, note-taking and re-reading the information that you have gathered needs to be imprinted in your memory cell for a longer period of time and to achieve that you need to explain others what you have learned. This will help you to recall what you have learned and by teaching it to others you will imprint the information in your memory for a longer period. And if you are finding it too difficult to recall some of the memory that you have learned, you can just go back to that chapter and re-read it to retain the required information.
By explaining the information to others, you get to know your strength and weakness of your memory and practice it is required accordingly.