To edit a guest's information on the Guest List App, find the guest you need to edit.
Tap their name. A window will appear with the full details and information of that guest.
Tap the field you wish to edit. When you are done with your changes, pull down the keyboard to apply the changes.
*Note: if a field is marked "Read Only" in the Registration Form, you will not be able to change that field in Guest List Admin Mode.