After finishing the book and making your personal index on the back endpapers, turn to the front and try to outline the book, not page by page or point by point (you have already done that at the back), but as an integrated structure, with a basic outline and an order of parts. That outline will be the measure of your understanding of the work; unlike a bookplate, it will express your intellectual ownership of the book.
Написать структуру книги. Тезисы. Это поможет лучше запомнить о чем книга
