Hi. @KimCoiffure! Welcome to the Square Community!
To answer your question, these reminders must be configured in the Square Dashboard on the browser. Once the reminders are set, the reminders will send automatically and you don’t need to adjust anything in the app. At this time, the mobile app doesn’t let you fully customize or create reminder templates; it only lets you view or toggle certain notifications.
I'm sure it isn't the answer you're looking for, but I wanted to provide some clarity! I hope this helps.
