Take a step back to reflect. You're chronicling your life lessons, but what have you learned from them? Relay your intentions, desires, feelings of loss, feelings of joy, the wisdom you've gained, and other inner thoughts from time to time throughout the book. Taking a step back from the action of the story to reflect on what it all means is a good way to add depth to your autobiography.
These are great tips! Especially about writing what comes to you, not the story you originally set out to write. Sometimes we’re smarter than we even know and something important is trying to come out! I also recommend checking out StoryShelter – it has lots of question prompts to get you writing about your life. See what questions get your attention and maybe do a free write around them to get the juices flowing!
Create an outline or a graphic organizer of the major topics and ideas you want to cover. For example, you might make a time-order chart -- a chart with event blocks to organize events chronologically. Or, you might draw a cluster web -- a diagram with connected circles -- to divide your autobiography into sections, such as one for relevant background information, one for life-changing events, one for special memories and one for goals and dreams. Focus on reasons why specific events, situations and circumstances were important to you and how they made you feel.