I found this book extremely helpful.

The book covers habits thoroughly, I like the science aspects of how habits and also tips and systems how you can improve and optimize them.

The magic of this book are all the examples and systems you can implement to habits which in turn improves your life.

Here are some of my favorite systems

• Build a system for getting 1% better every day.
• Overcome a lack of motivation and willpower.
• Develop a stronger identity and believe in yourself.
• Design your environment to make success easier.
• Make tiny, easy changes that deliver big results.

The author has a ton of resources on his website that link to the lessons and principles from the book making it very practical applications in your life. If you are visual person like me he has many info graphs that help explain the key concepts.