You can actually write about your hobbies mostly the things you can write in which you are interested in. if you want to elaborate the topics you can choose one of these-: 
teaching- i lik to teach children without fees and  all
playing- you want to be th world's best cricketer or any other sportsman
reading book and novel- in this u can write that what good books u read. how it helped u, what learnings u get from it, or how did it increased ur vocubalary