As strange as it sounds. I think people really improve just by reading the book.
Imagine one day you find an itch on your little pinky on your left foot. You never notice it before. Now spend all day thinking about it. Every day. It will be magnified, it will become unbearable. I think the book teaches you to shift your attention.
Sometimes just reading the book causes things to change — in my case, symptoms shifted to a different area (a-ha!). Think of it as "telling" your mind that the game is up: you know what it's up to.