Navigate to the Account Settings page by clicking on your name in the top right corner
Select the Users tab on on the Accounts, Users & Entities table
Each line item on this table contains a user, and that user's permission type on a specific account. Identify the user/account relationship you would like to edit
Select the Pencil icon on the right side of the table, under the 'Actions' column
In the Edit User Permissions pop-up, select either 'Update Role' or 'Remove Access'
If you select 'Update Role', select the new role from the 'New Role' dropdown on the right
After making your selections, you can select 'Apply these changes to all of [user]'s accounts' to apply the change to all user/account relationships
Click Save
