Reminder messages (email and text) have a standard format automatically populated by your SignUp information and includes the Organizer Email address, the Location, and specific assignment Spot information (the Description, Date, Time and Extra Details).
There are a few ways to customize Reminder messages:
1. Changing the Spot information in the Spots tab of your SignUp's Organizer. You can add several sentences of instructions and include links to important information that will be included in both the Participant's Confirmation and Reminder message. Please see: Can I attach a Zoom meeting link, document or map to my invitations, confirmations or reminders?
2. Adding a line of text or a link to an important document, map or online meeting that will only be included in Reminder messages (both email & text). Do this in the Settings tab/ Email Preferences screen. Please see: How do I change my SignUp's Organizer Email Preferences?
3. Updating the Location information in the Details tab of your SignUp's Organizer view.
Also see: When are emails sent from SignUp.com?