While you might not remember every detail about a certain event, I guarantee someone who was there does remember. Asking family and friends for ideas or details of a certain situation can give you a completely different perspective of the event or time in your life. That perspective might prove to be invaluable in your writing. Be prepared; once you get a group of family and friends together to reminisce, you will be shocked at how quickly the ideas come and how one idea can spark another and another and another.
If you are not sure that your whole life path is worth attention, then a memoir is your best choice. It is focused on one particular event, relationship, place, or period of your life that has influenced your personality a lot. Don’t be afraid to express your personal feelings and ideas in your memoir, as it shouldn’t be simply a brief list of facts, but the reflection of your inner world.
Writing an autobiography for a high school or a college English class can help you gain a deeper sense of personal identity. An autobiography allows you to tell your story in a way that reveals truths about your values, goals and dreams. Though there's no exact science to writing an autobiography, you should include information about your background, major events that shaped who you are and any core themes in your life. Include specific examples to help readers understand your life history.