Under your Settings tab, click on Notifications. In this tab, you will see each of the templates laid out for booking confirmations, booking cancellations, rescheduling notices, and booking reminder notifications. Feel free to go through and customize these as you wish! You will see the pre-set buttons below each template, by clicking on these they will automatically add in the link/title in correspondence of what they say.
If you are not wanting a notification to go out for each of these topics, please click on the box beside "Is Active?" below the template box. By unchecking this box, this deactivates that message from being sent out.
At the bottom of this page, below the Booking Reminder template, you will see that you can custom set how many hours before the upcoming booking you would like for this email to be sent out.