How do I allow users to edit their own User Groups?

Select the "User Management" tab located in the left navigation bar, and then select the "User Groups" sub tab in its dropdown bar.
Select the greyed out toggle directly under the "Create User Group" button on the top right of the page.
You will know this has been set up correctly once the toggle changes to your brands colour and the below prompt appears on screen.
When enabled, users can now go into their profile and edit what User Group they are a part of on the platform. The ability to create new groups, rename existing or delete user groups will still be restricted to specific admin accounts.

After reading this article, you'll be able to allow users on your platform to edit what User Group they're a part of.