You may either use {{SULcheck}} by itself for the default message or you may add a custom message as an optional parameter. Placing {{SULcheck}} on a talk page makes the following appear:
This template adds a multilanguage logo with text. It is for use on the [[Wikipedia:Project namespace|project namespace]] to alert editors to review the [[WP:SUL|Single User Login]] information of an editor.
Any of the following inline, comment-level templates can be converted into {{Resolved}}-style hatnotes by using {{Resbox}} to put a box around the icon and text.
{{enUici|Wikipedia:List of discussion templates|List of discussion templates]], a more linear table of essentially the same set of templates
Template:Resolved/See also, the smaller family of thread-level hatnote templates, similar to the above but with a box around them; any template above can be converted to one of those with {{Resbox}}