Pink Lady,
If I to pick one piece of advice for a new teacher, plan your lesson from what you are exactly going to write on the board, handout, and even say, and plan at least 2-3 exercises...always...every class. I've had some lessons that I spent hours on, and my students ran through them in mere minute. Then you're left with nothing. If you over plan, you will always use it in the future. It will not be a waste! AND HAVE FUN!! I don't understand all this 'you have be to so strict and stern'. My students are learning quickly and we are having a blast. By far, we are the loudest class in the building!