One of the best ways to retain what you read in any book is to adopt the following system:

1. Read a section or chapter a day in order to get the full impact of the content.

2. As you read, underline what strikes you as important or unusual.*

3. Write personal comments along the margins.  Use the front and back pages for lengthier comments.

4. Place a question marks next to items you need to check on.

5.  When you finish reading the whole book, review all your notations.

*Many say they cannot underline straight. Use a mechanical pencil: GRAPHGEAR 500 from 0.9 Pentel (available at most office & art supplies stores).  Hold it towards the top and you will get an almost ruler straight line.  Yellow highlighters fade.