Roles could be things like "Shift lead", "Cashier", "Cleaner", "Volunteer" for work shifts, or "Host", "Speaker", "Worship leader" for church services.
Choose the dates and times of your occurrences including any details like the name of the event/occurrence, location, or any other details you want to include.
Finally, click the "Create Rota" button on the bottom right hand corner to save your rota.