To downgrade an Supervisor to a standard User you must currently be a site Administrator for your organization.
Here's how to:
1. In the Administration section, select Manage Users.
2. Click the green Find Users button located within the Manage Users section
3. Select the Users from within the section '2. Select Users' list and click continue.
4. Click on the name of the person you wish to downgrade.
5. You will notice that the edit option has been removed next to User Type. Select the Access Tab from the option bar to alter the Users access settings.
Note: if there is no Access Tab it is because that user is a site Administrator.
6. Within the Access Tab you can remove all Functional Access by unchecking the boxes, as well as clearing out the selections within Groups User Oversees.
7. By removing all access options and selecting save at the bottom the system will automatically remove the User Type of Supervisor and replace it with User.