Don't expect someone to tell you something you need to know unless you ask. Most teachers and administrators are happy to help, but they are busy and won't think about telling you everything.
While you want your classroom to be comfortable, don't stress out about making it look perfect. Spend the majority of your efforts planning how your classroom will run and not how it will look. Put most of the money you spend into making it organized, efficient, and easy to run. Here are some books that I consider to be "must reads" when setting up your first classroom.
It's okay if the kids don't always like you. It's not okay if the kids don't always respect you. You want to be their best teacher and not their best friend. Being firm, consistent, and having established routines and procedures will allow you to plan fun activities without chaos over taking your classroom.
Relax. Find humor in your job. There will be situations you didn't expect and for which you weren't prepared. You will make mistakes. Admit your mistakes, learn from them, plan how to avoid repeating them, but don't beat yourself up about them. Learn to laugh. Tomorrow is a new day and a fresh start.
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