Brainstorm all the major events in your life. At this stage, do not censor yourself or limit what you want to say. If a memory is meaningful, add it to the list.
Read through your list and highlight the top few moments that you want to cover in the condensed version of your autobiography.
Create an outline to organize these major events into the order you plan on writing them. Decide if you want to structure your autobiography chronologically or by theme.
Write the first draft of your autobiography. Try not to edit while you are writing the draft: Just get all the stories down onto paper or your computer.
Read the first draft and make notes in the margin. Think about places where you could tell a more vivid story and then correct grammatical mistakes.
Repeat the editing process at least one more time, or until you feel that you have given a clear picture of who you are.