Alfred,
My advice to you is just follow the process. My other problem was not thinking of the kinds of questions I wanted answered by the material I was reading. (I still forget and do that sometimes and when I do it doesn't work as well.) My solution for that is to take the subheadings, if there are any, and ask myself what the subheading has to do with the chapter title. Then I look at the chapter title and ask what that has to do with the book title.
I read mostly instructional materials and rarely read novels or other pleasure type reading.