Follow this guide if you created your SharePoint site without the help of the template provided by ITS.
This article covers how site owners can remove, others from a SharePoint site.
Navigate to s.uconn.edu/sharepoint.
Click on your site, then click on [#] members in the top right.
Find the member you would like to remove and click the dropdown arrow next to their membership status (this will say Owner or Member).
Click Remove From Group.