Many users like getting an "immediate" reminder for themselves or for their team members so all staff are aware of new appointments.
To get immediate reminders for a new appointment when it's created:
Go to the Settings page.
Find the "Reminder Yourself Too?" section at the bottom of the page.
Select email or text reminders from the first dropdown.
Select 30, and then Days from the other dropdowns.
Now, as long as your appointment is not more than 30 days away, you will get an immediate reminder whenever a new appointments is created.