Be flexible and ready for new experiences. Don't lock yourself into a specific grade preference. Also, just be yourself with the kids and expect to have good and bad days. Be willing to admit ignorance. You won't ever know everything about everything.
Teachers are like caring machines, both for children and other teachers.
There is a spirit of camaraderie among us, and we are more than willing to share ideas. You never know what idea will spark something for you. I would encourage all juniors and seniors to register with local boards of education, and to do some substituting on school breaks . I believe it is very important to establish a classroom discipline scheme from the outset. Make it clear to students that you are not there to be just their friend, but their teacher.