I’d suggest taking a screenshot of the home page and going through what each element does (including the menus under the upper right buttons). And again for a particular topic. The welcome message goes through some of this, but in small pieces rather than holistically.
This is for “howto” pages about Discourse, hence the Meta category. We might need a requests-for-documents topic for the stack itself, too (or is there one already?).
Asking for help and how-to information is the intention of community.lsst.org’s Q&A category. There have also been some un-prompted how-to articles written in the Data Management category, e.g.: Developing Software with the DM Stack
Questions and content that appears organically in this community will eventually be incorporated in the new LSST Stack docs.