You can mention the following:

1. Your hobbies
2. Your personality
3. What you wish to become in future
4. Your passion and goals
5. Your social interactions
6. How you typically spend your leisure time
7. What you like and don't like
8. How you resonate with school or college
9. What are you currently looking forward to

Make sure to give a catchy start to the essay to grab extra marks.