Regarding how to read and how to read, Mr. Zhu Guangqian mentioned in Twelve Letters to Youth:
First, all books worth reading must be read at least twice. Read quickly for the first time, focusing on awakening the main idea and characteristics of the whole article. Read slowly for the second time, and measure the content of the book critically.
second, after reading a book, you should note the outline, wonderful places and your own opinions. Taking notes can not only help you remember, but also force you to be careful and stimulate you to think.