The lesson
Write the setup guide for a new feature as a product page: start with what it is, then permissions, then its settings with screenshots.
The Reviews guide opens with an Overview and a keyboard path (press G then R). Setup is split into Organization setup and Personal account setup, each with a product screenshot. Later sections walk through display options, GitHub labels, Guides, and Unified versus split diff, with a right-hand outline listing the subsections.
Don't copy the exhaustive depth if your feature is small; a guide this long suits a feature with many settings. Keep the owner-versus-user split and the in-page outline.