I fill one out for each one of my kids and laminate these cards. I keep them in my room and when a student needs to go to the restroom or get a drink I will punch it. This works well for students who have time between classes but seem to think that class time is when they should take care of these necessities. At the end of the semester, I give a piece of candy for every star they have left. I punch their cards and we start second semester.
I color code my different subjects, so this has five different colors. It is in Word format so you can edit for your particular needs,