Rule 1: You must know what kind of book you’re reading. Find this out early in the process.
You should be able to state what the book is about.
Is the book a theoretical book or a practical one?
Classify the book during inspectional reading if possible. If you can’t figure it out from the title, TOC or index, then read key summary passages.
Practical books often say stuff like “should”, “ought”, “good”, “bad”, etc.
Every book has a skeleton. Your job is to find it. Every book worth reading has a unity and an organization of parts.
Rule 2: State the unity of the whole book in a single sentence or at most a few sentences.
Rule 3: Set forth the major parts of the book, and show how these are organized into a whole.
Each part has its independence. But usually is also connected to the other parts.
You may be able to get the unity from the title or preface (if the author is cool that way). But be alert in case he is wrong. He may claim one thing but deliver a different unity.
At the end you should be able to say: The whole book is about so and so and such and such. The author accomplished this plan in five major parts, of which the first part is about so and so, the second part is about such and such, and so on. The first of these major parts is divided into three sections, of which the first considers X, Y and Z, etc.
This is the ideal. You will often not reach for this ideal. Clearly, many/most books are not worth it. You’ll make an approximation of the above for only a few books. Also, if you cannot come up with this, it is more likely the fault of the book and not you.
Rule 4: Find out what the author’s problems were.
Once you’ve followed these 4 rules, you know the structure of the book. Keep in mind that there’s no law that states you need to follow these 4 rules first before moving on! You can do this simultaneously with the other rules coming up.