Here is a layout design of a Self-Help book. As for me, this is a simple style that needs some corrections. But it worth your attention.
It can give you an idea of how to make your book look amazing and professional. The title of the book is “Cleaning Up Your Mental Mess: 5 Simple, Scientifically Proven Steps to Reduce Anxiety, Stress, and Toxic Thinking” by Dr. Caroline Leaf.
You can find this book on Amazon.com