Go to your Admincp
Open Usergroups Menü
Usergroup manager
Press edit on the usergroups you want to be colored
Username HTML Markup
For example, if you want the names of the chosen usergroup to be in bold, enter the following in the first field:
Second Field:
If you want the names to be italic and underlinded, enter this in the first field:
Second one:
To display the nicknames in colors, enter the following for the first one:
Second:
Where you can edit the red, for example to blue, green or anything you want
Regards