QUOTE(dcmbarton @ Aug 29 2007, 01:49 PM)

What a minefield! I'd say that most importantly, when you start teaching, you are affecting people's education, and that's not something to be taken lightly. You cannot just treat it as an experiment, and you have to approach it in a totally professional way. It can't be seen as something you 'do on the side'. It takes a lot of preparation, reading, planning, learning and communication before you even teach your first lesson.
David
Totally with you and prepared for the first explosion
If you don't have the slightest idea where to start at all, better don't do it yet. It is not enough to be just a good performer yourself.
Maybe you could start teaching under supervision instead? That will give you more confidence, you won't do any harm, and you will learn a lot you can use later on ...