The Payments Preferences screen can be accessed from your dashboard by clicking on the vertical ellipsis ( ⋮ ) on your Payments App and selecting Preferences.
The preferences menu allows you to choose the email templates sent out from the Payments App.
Customer Email Notification Template - the template for the email sent out to contacts when a payment is entered (unless the contact is flagged to opt out of billing emails).
Internal Email Notification Template - the template used for the notification email sent to the Method:CRM User assigned to the payment.
Note: You can create custom email templates using Method:CRM's Email Templates App.