When viewing the list of Newsletters on a wiki the software should provide a help link to the help documentation at Help:Extension:Newsletter
User-facing documentation best practices indicate that the software interface should link to help documentation when possible. A consistent way of doing this in MediaWiki is by providing a "mw-indicator-mw-helplink" on the Special: page like Special:Search, Special:Upload, etc.
This applies to all Newsletter interfaces, not just the main listing. The pages for announcing and creating new newsletters in particular would benefit from references to help documentation.
See the upper right "?" Help link in this LTR mockup