I like what gfell already posted as a really good guide.
I usually begin every class with this skeleton to hang things on.
1. Review (tough on the first day, but try to find out what they should have learned last year and just go over it again - for a first lesson, this could end up being a whole day's worth of teaching, but don't - you should cover new material.)
Review is good for every day. Repetition is the key to learning, so if you preview today, teach tomorrow, and review the next day, they have a better chance of "gettin' it".
2. Cover new lesson material through repetition exercises - repeat after me for the whole class, one by one around the room (gives them a chance to speak and hear other students; gives you a chance to determine student levels pretty quickly).
3. Cover new material. Curriculums are very lacking in China, at best you get thrown the most popular selling English book on the shelves that year. Lot's of creativity required.
4. Assign homework and go over your expectations so that students understand how to do it.
5. Preview the next day's lesson. Something brief, but something they can take with them. A game that can introduce the next days lesson is great - games can also be used to review at the end of class, but I prefer to preview tomorrow's lesson today, and review today's lesson tomorrow. (That come out right?
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