Adding a new client does a few things:

  1. Makes that client available in dropdown menus for copying + browsing templates
  2. Creates a Drive subfolder for that client, to which any new template copies will be added
  3. Creates a Client Workbook copy for that client

You can add new clients from either the 'Project Management' menu, or from the link within the 'Copy Template' form.

If you're no longer working with a client, you can deactivate them at any time from the 'Client List' at the bottom of the sidebar.  This will not delete their files, but it will remove them from your Add-on dropdown menus.

Important to note: you will still need to connect your Client Workbook to the PM Tracker the first time you open it, by 'Allowing access' from the Getting Started tab.