I have officially tutored in math and physics in high school. It was like one hour a week after school. Basically I would go over their homework with them and explain things they did not understand. Not so bad. I tutored two people at school and private tutored one o my friends (her parents insisted paying me to my dismay). My friend was pretty easy to tutor since it was more of once she knew what was going on, she understood it.

"Unofficially" I would help my neighbour in Chem, basically I would go over and help her with her homework, explaining things and making jokes when she defied the laws of nature (not in a mean way, we both laughed). I was also known as a go-to before a test. I had literally once opened a textbook and gave an abridged version of Canadian history. The latter was not so much tutoring as leading a cram session. I personally liked helping people because I find it is only when you try to explain it that you can truly know if you understand the material.