Let your students set the tone for the semester by developing a community agreement together. Here are some tools to get started.
National Education Association: Creating a Community Agreement
http://www.educationalimpact.com/resources/etdc/pdf/3A_CARE_Activities_Resources.pdf
How to Crit: A resource by Mitch Goldstein
10 Rules for Students, Teachers, and Life
https://www.brainpickings.org/2012/08/10/10-rules-for-students-and-teachers-john-cage-corita-kent/