Start with just one or two mind probing questions. If you don't have a question in mind there's no point in activating. You don't want anything from the book.
Also try skittering books like textbooks rather than superreading. Technical text and page long paragraphs makes superreading less effective. You're not looking for your trigger words as such. Your trigger words are used for creating questions.
If you don't know the exact information you need you probably need to check your purpose for the book. The big picture is good, now see the book as one of the sub-goals that will help you reach that big picture. What can you learn from the book? How do you see yourself using that information. What information is it that you see yourself using? Now your purpose is to get that information conscious so that you can use it and move on the path toward your big picture.
Alex
