To access your Collaborator List, simply tap on the blue avatar in the middle of your bottom bar. You'll now see the list of Collaborators on your Production.
Select the Collaborator whose permissions you'd like to change.
In the Collaborator dashboard, select the new permissions you'd like to assign this Collaborator, or tap "Remove Collaborator" to remove them from your Production.
Once you've removed the Collaborator, they will be removed from your Collaborator List, and the Production will disappear from their personal Show Library.