This article explains a simple method that helps to reread books in 30 minutes or less. Whenever you wishe to reread a book to refresh your knowledge, you can apply this method and save an enormous amount of time.
1. Read the book
First, you have to read the book. It helps to schedule reading time and reduce distractions during this period. Personally, I like to go to libraries as everyone else is studying there as well. When reading a book for the first time, you can apply speed reading techniques, such as meta guiding. It is when you use a finger (or a pointer like a pen) to guide your eyes to specific words. The point is to decrease distraction and focus on the specific words to increase your reading speed.
2. Underscore sentences and passages
When reading the book for the first time, underscore the most important sentences or passages. The more you read, the better you will understand which parts are important and which not. I usually underscore parts that are insightful and teach something new.
3. Use page markers
Whenever you underscore more than one sentence on any given page, use a page marker (also called sticky notes). You can find them in every stationery department and are worth every cent. Personally, I like the ones from Post-it, but every other brand serves the same purpose.
4. Start rereading
Now that all pages are marked with sticky notes and important parts are underscored, you can start rereading the book. You just have to go through the page markers and reread the underscored sentences and passages and skip the less important rest. It depends on the amount of underscored pages and on the book length, however, I made the experience that it does not take longer than 30 minutes to reread a 300-page long book.