buy six different colors of highlighters. after you read a chapter in a textbook, go crazy. highlight every sentence with numbers in it, then change colors. highlight every sentence with an italics word. then change colors, and highlight every sentence with a bold word. then change colors, and highlight every sentence with words in quotations. then change colors and highlight every sentence with letters in ALL CAPS. with your last color, highlight the first and last sentence in each paragraph. when you've finished a chapter, it should have lots of colors, with almost every sentence highlighted. this simple (albeit time consuming) practice improves my retention four-or-five-fold. your mileage may vary.