Neal, as a high school student, I can give you this advice:
Keep class interesting. Mix it up. Come up with new ideas. Consider suggestions from the students. Really get to know the students. Be a friend to them. If there's a kid who doesn't like you and he shows it, feel free to use humorous insults. The rest of the class will love it. Don't be afraid to throw some fun things in the mix every once in a while.
Also, try to get to know a bit about what the kids like.
My old history teacher was an awesome guy. I loved his class. He did stuff like this. He'd go out of his way to make sure we learned something in the chapter. I'm thinking of calling him to ask him if he'll come back since Ms. Communist resigned this week.
Do you know what you will be teaching?