Choose an accomplishment that was truly important to you. This doesn't have to be something huge, such as getting promoted to vice president at the age of 23, but can be something more modest, such as running your first half-marathon.
Provide an in-depth explanation of how you reached your most amazing achievement, if it is something the reviewers can learn about you from your resume. For example, if your greatest achievement is earning a 4.5 GPA in high school, explain how hard you worked in Advanced Placement courses, and how much of your free time you sacrificed to make this goal your priority.
Choose a volunteer organization that you worked with, if you presently volunteer, or have in the past. Explain a situation that you encountered and participated in during your time there that made you proud, or even just the pride you have from volunteering there. Explain how you got involved in the organization, and your volunteer role there.
Describe a risk you took that you were initially unsure about, but went for it anyway. Explain what motivated you to take this risk, and why you are glad that you did it. This could be a challenge that you met such as packing up and moving across the country to take a new job, or putting yourself out there by entering a painting in an art competition even though you're extremely shy about your work.