Many schools ask the students to move the tassels in unison, so everyone shares in the moment. In other ceremonies, each student moves his own tassel after accepting the diploma. Ask a teacher if you are not sure which tradition your school follows.

Unless specifically told that you can pick your own tassel, stick with the default recommended by the school.

Some high schools will allow you to decorate the top of your mortarboard. Make sure you stay within the provided guidelines, or the school may remove the cap.