If you are interested in giving style sheets to the Usemod Community, please put the code for the style sheet in a subpage like it is done below.
You may also indicate a link to a site where the style sheet is showcased so we can all see the marvellous style sheet.
As a Usemod User
Just save a style sheet on your hard drive with the extension: .CSS and at Preferences, indicate the address of the style sheet URL and Usemod will do the rest.
This way you can see any Usemod site with the style sheet of your choice.
As an administrator
Do the same but save the CSS on your site.
see also WikiBugs/CSSFormatting