Psycho-Cybernetics, Updated and Expanded

Most complete book about the subject. If you're really serious about improving yourself I think you'll benefit a lot by doing all the exercises and studying it extensively.

There is that one chapter near the beginning of the book that tells you to read it multiple times over the next few weeks for the information to stick, it really requires extensive study and much repetition to get the most out of it.

Thus I feel it requires setting everything else aside and solely focusing on this one book and all information presented, and your transformation may begin.