Here's some great ways to get started with writing your autobiography or even writing a biography of a loved one. 

1) Talk about the people.  The people who shaped your life are going to be an important part of your story.  Parents, grandparents, siblings, close aunts and uncles....these are people worth writing about. 

2) Childhood memories are worth recording.  Your best friend, your favorite climbing tree, your school experiences, and your favorite TV shows.  All details that need to be captured....and you'll be surprised at how the process opens a door to more memories. Explore all your senses.
3) History has really touched your life.  No matter your age, there has been political events, wars, life-changing experiences, wonderful accomplishments in technology, and much more that have shaped history and your own life.  These need to be documented in your personal history (you're becoming your own personal historian!)--better than a history book. 
4) The real world of adulthood needs to be captured.  Love, marriage, children, grandchildren, pets, volunteerism, your favorite charities, and more.  What makes your grown up life great?  This is something that also deserves to be in your biography or the biography of a loved one. 
5) Bring it all together -- Be sure your values, beliefs, life lessons, and more are there for your family and friends to read today and in the future. Genealogy is great, but the essence of who you are needs to be recorded.  You and the people who came before you are worth remembering.   is a great resource if you need some help with a guided biography method.