Building keystone habits is crucial for creating a ripple effect of positive changes in one's life. Keystone habits are those that have a significant impact on other areas of our lives, often changing our self-image and behavior without requiring extra effort. Examples of keystone habits include exercising regularly, cooking at home, and getting up early. To identify your own keystone habits, look for behaviors that have a ripple effect, changing your other behaviors in unexpected ways. Once you've identified your keystone habit, make it easy to stick with by planning ahead, making it tiny, and overcoming resistance. By doing so, you'll build momentum and create a new self-image that will help you perform the behavior without even thinking about it. Ultimately, building keystone habits is a long process that requires determination but yields overwhelming rewards.