Read other people's autobiographies to get ideas on how you can write your own. Go to the library and take out as many different books as you can, as there are many different types of writing styles that can help you to get a good feel for how to write an autobiography that will suit your life's story.
Keep a journal or diary and write about your daily experiences and how you felt when significant events occurred. If you have a journal or diary from your childhood, skim through it to remember events that happened in your life in your younger years.
Determine your key audience. Writing for your family requires a lot less detail than if your audience were the general public, who don't already know you. If you are writing for the public, your voice will be a lot more formal, with much more detail given when you recall events.
Choose a particular core theme for your autobiography that guides your life throughout the story. Is the story about your life life? Is it about a lifelong dream you have had? Is it about a treasured friendship that changed your life? Deciding on a core theme will bring continuity and therefore spark interest in those reading your autobiography.
Decide on a starting point for your autobiography. Will the story start with your birth, your first day of kindergarten or how you met your first love? You can choose to write your autobiography in a chronological order or by describing particular big events in your life.
Look through old family photo albums and talk with family members about significant events that happened in your life. This will give you more ideas and will spark some humorous and sad memories.
Get organized by writing notes in any manner you wish (e.g., in notebooks, on the computer) and keep them neat and organized. Also, set a deadline date for finishing your autobiography.
Write your autobiography. Be honest and descriptive without overusing detail. Using just enough detail helps your story flow better and makes it more readable to your readers.