[2-3 sentences on your path into aviation. What got you into flying, how long you've been at it, any relevant background before instructing. Keep it personal and specific rather than generic, this is the paragraph that makes you a person instead of a certificate number.]
Example shape: "I started flying at [age/year] and haven't stopped since. Before instructing, I [relevant background, e.g. flew charter, worked toward the airlines, built time cross-country]. Somewhere along the way I realized teaching was the part I loved most, so here I am."