Thirty six for zero!!
Oy oy oy!!! Your question is breathtaking, boundless!!
I am, by trade, a tutor – i.e., I teach either individuals or small groups.
I produce most of my material as I go, drawing on a collection of gathered-over-years material and standard textbooks (and a grammar of my own). It’s hard, but satisfying. You need a contract that remunerates you for preparation, or you’ll drop dead after a year or so.
I develop my ‘curriculum’ on the basis of a continuing analysis of (a) the problems that the students have, and (b) the goals that you must reach in the provided time – and knowing the standard to be reached is critical. I then write material that deals with the difficulties that the students have.
Please do post further texts on this subject. I am always eager to learn, and I’d like to know how you get on.