Choose a moment in your life which defines your identity. First, you need to determine which of your identities you are going to write about: musician, scholar-athlete, mother, son, etc. Then, choose the moment in your life which really is the best example of when you felt this identity the strongest.
This essay will *not* have an introduction, body, and conclusion. In fact, it will have very little "narration"...instead, it will be be a *scene*. Simply start writing at the time and place when this event happened and describe it as well as possible.