Understand the memoir genre. In a memoir, you are the main character of your own life story. Many memoirists use the facts of their life story to create an engaging tale for the reader. Because you are relying on your own memories as source material for the story, you may end up describing things differently than others might remember it. The key is to write down things as you remember it, in the most honest way possible. Keep in mind memoirs are different from autobiographies in that memoirs should only cover certain key aspects of your life, not your life from birth until the present day.
After considering these factors, the next step is writing a draft. Start by looking through the best autobiography openings you can find and figure out which you can use as a model. Make sure that you write in the first person since that’s what autobiographies are all about. Never switch back to second-person or third-person and be consistent in using the first person point of view throughout the entire content.
These two sets illustrate how you should show the entire action and then show the entire reaction. Don't mix the two together in one paragraph. Write your entire book in this way — action and reaction, one complete set after another. If one part of the set is missing, readers will sense an awkwardness. If you're writing an autobiography, or anything else, action/reaction sequences will make your writing lively and natural. As you expand your ideas, write in action/reaction pairs.