Procedures. The first few weeks of school is all about teaching rules and procedures. Your students need to know the expectations and procedures foe EVERYTHING you do in the classroom. Be very clear on how you what your students to line up, ask to use the restroom, sharpening pencils, etc.
Make sure you compliment your students for a job well done. Students respond better to praise than to negative feedback. The more time you take to teach them the procedures, the smoother your school year will go. Make sure to MODEL, MODEL, MODEL.
Don't try to do it all. There are so many great teaching ideas and resources that we want to do them all. This is not realistic. Choose a few new thing to try each school year and do them well. If you try too many new things, it will not work.
Become friends with your custodian and secretary. They may a time when you are in a bind and you need the help of your custodian and secretary. They are more likely to help them if you take the time to know them and treat them with respect. Give them a little treat from time to time and let them know that you appreciate them.
Be positive and make a connection with your students. Many of my students do not get the attention they need at home. My most difficult students respond the best to me when I take the time to get to know them and I am positive with them. They know that I truly care about them and want what is best for them. Being positive with your students goes a long way.
Find time for yourself. You can easily run yourself down and get teacher burn out. Take a break and read a book, go to a movie, or find a hobby. I take dance classes on a regular basis so I get plenty of exercise and hang around people that aren't just teachers. I love teaching but I don't want to be talking about it all of the time. It is important to find some time for yourself to stay healthy and happy. Teaching is HARD and DEMANDING work but the rewards are well worth it! I could not imagine doing anything else.