While I didn't apply for this, a substantial number of students in my grade did, many of whom were successful. For their reflection, they focused on how their chosen activities were enriching learning experiences. Generally speaking, it's really good if you have a wide range of activities e.g. volunteering + competitions + sport, as that way you can hone in on many different skills e.g. interpersonal, communication, teamwork skills. I would also recommend discussing any problems/challenges you may have faced and how you overcame them to highlight your resilience.
