If the template has a separate documentation page (usually called "Template:template name/doc"), add
[[Category:24 user templates]]
to the <includeonly> section at the bottom of that page. Otherwise, add
<noinclude>[[Category:24 user templates]]</noinclude>
to the end of the template code, making sure it starts on the same line as the code's last character.
Note to users who subst: user templates
After you save the user page, please edit it again to insure that no user template categories have been placed on the user page. User pages are not user templates, so they do not belong in user template categories.
Pages in category "24 user templates"
The following 14 pages are in this category, out of 14 total. This list may not reflect recent changes (learn more).