When I read books, I bookmark all of the items within it that interest me and seem like I would want to learn. Then I go through each item one at a time with cards in hand and follow along, making sure not to go to the next step until I fully understood the last one. It's basically patience; take your time and don't rush anything. I think it also helps to have a notebook and take notes as well. I've done this a few times and it's helped me tremendously.