Once you add your class or classes to the site you are good to go. I have found that starting each day's attendance on the website and then tracking through the app allows for the greatest usability. I love the ability to apply my custom points to one, several, or all students. An even better function is the random button. This function helps you to switch up your participants and tracking (think of it as pulling sticks).
ClassDojo not only allows you to review the behaviors collected, but you can also share the data with parents and students.
Do you use ClassDojo?