Thread:AdorableDarling/@comment-29484493-20161011220053/@comment-27345308-20161015105735

You need to go to one of the  pages and edit it. For example, to change how "Admin" displays for administrators, edit MediaWiki:User-identity-box-group-sysop. However, not all pages of this kind are editable and you might need to contact Staff to change some of them.

Other way is to use UserTags, like the linked wiki did use. All documentation about that script is on its documentation page.