Hi, I'm 27 and I teach English kind of as a hobby. :)
I have CAE C1 certificate from British Council and during last 3 years I have been teaching kids English in English. We start as young as age of 4 and we go up to the big ones. We play a lot of games, we build things, we create. The grammar comes along with understandings, as is natural in any language. With the youngest kids we learn how to read English and how to play with words, how to understand. And we have fun!