You may not have had the most interesting childhood in the world, but everyone has had a few memorable experiences. Highlight the best parts when you can. If you live in a big city, for instance, you should realize that many people who grew up in the country have never ridden a subway, walked to school, ridden in a taxi, or walked to a store a few blocks away.
Train yourself to use concrete details rather than abstract concepts. Take another leisurely look at what you've written. Highlight abstract phrases such as "I was afraid," or "we had a pleasant time." Replace these abstract words or phrases with something concrete, such as "my hands shook and my mouth felt stuffed with cotton" or "We drank Chardonnay on the Chatterley's sailboat, and as the sun set Rachel and I walked hand in hand along the boardwalk." Was it "a hot day," or was "the asphalt so hot that your flip flops stuck to the tar"? You might go back to the professional autobiographies you're reading and type out a few passages from the books for practice. If you're watching for it, doing so will focus your attention on the concrete. Most ordinary readers won't think about whether or not you've used abstract or concrete terms. They will know whether the writing is boring or interesting. Writing an autobiography with concrete specificity will only improve it.
"Most people don’t think of spiders when they bite into a tomato, but I do. Growing up in southern Ohio, I spent many summer afternoons picking baskets of tomatoes that would be canned or frozen and preserved for cold winter’s dinners. I loved the results of my labors, but I’ll never forget the sight of the enormous, black and white, scary-looking spiders that lived in the plants and created zigzag designs on their webs. In fact, those spiders, with their artistic web creations, inspired my interest in bugs and shaped my career in science."
Sometimes people come into your life and you know right away that they were meant to be there, to serve some sort of purpose, teach you a lesson, or to help you figure out who you are or who you want to become. You never know who these people may be (possibly your roommate, neighbor, coworker, longlost friend, lover, or even a complete stranger) but when you lock eyes with them, you know at that very moment that they will affect your life in some profound way.
Incorporate dialogue into your autobiography to make it more personal, recommends history professor Robert Gerlich at Loyola University in New Orleans. Consider including humor when it's appropriate. For example, if you're writing about how you got lost at Disneyland when you were 10 years old and how the experience helped you learn to face obstacles, problem solve and overcome your fears, you might write, "The attendant at Splash Mountain said, 'Are you OK? Did you get separated from your family?' I quickly replied with as much bravado as I could muster, 'Nah, I'm fine. My eyes are just wet from the ride.' I didn't want her to know I was crying."