Brian Colbert has written a book called The Happiness Habit: choose the path to a better life. It is excellent. It is very well written. It provides lots of useful tools to help sharpen your thinking and to help people make decisions about issues or challenges they face. The exercises are simple to do and insightful. The book is published by Newleaf, an imprint of Gill and Macmillan. I highly recommend it. I read it and did the exercises in less than two days. It grabbed and sustained my attention. A superb book.