At this point in the proposal process you must write down all the reasons why you are the best person to write your book. This section is called “About the Author.” It, again, falls under the Introduction.
Sounds pretty simply, right? It actually is.
Write a biography of your expertise and experience in the third person tense. Include the most important facts first, such as anything that makes you the expert on your topic, your educational degrees (if they apply to the topic), work experience, etc. Include all your achievements. See this as your resume in prose but written specifically for your book.
Include a professional head shot if you have one.