If you want to have a general idea on which customers attend your classes or events, you can do so by changing the Attendance options in Settings.
You can do this by:
- Going to My Account (Gear/Cog)
- In Settings > Events
- Scroll down to Attendance > Change to False by Default.
This will now reset all the Attended checkboxes in your Attendees list to an unchecked box.
Now if you go to your Attendees List for a given event (this can be accessed quickly by clicking on the "x of x taken" link on the dashboard calendar) you can select the tick boxes and using the drop down menu, select Mark as Attended.