diff --git a/documentation/how-to.md b/documentation/how-to.md
index 2a12ac966..2283c817c 100644
--- a/documentation/how-to.md
+++ b/documentation/how-to.md
@@ -321,6 +321,45 @@ as before, and an embed that passes a token keeps getting Mapbox under `auto`.
 
 ---
 
+## Show a different people-group list
+
+Every map shows DOXA's people groups unless you ask for another list — same bundle, no rebuild.
+Resolution order (first defined wins): `profile-config.list` → `?list=` in the page URL →
+`window.MAP_LIST` → default `doxa`.
+
+| `list` | also accepts | shows |
+|---|---|---|
+| `doxa` | `2000`, `project-2000` | Project 2000: DOXA's people groups |
+| `unreached` | `7000`, `project-7000` | Project 7000: unreached people groups |
+| `frontier` | `4700`, `project-4700` | Project 4700: frontier people groups |
+| `frontier-500k` | `700`, `project-700` | Project 700: frontier people groups of 500,000 or more |
+| `unengaged` | — | Unengaged unreached people groups |
+
+```html
+<!-- per embed -->
+<my-map profile-config='{"profile":"my-map","list":"frontier-500k"}'></my-map>
+
+<!-- or flip any generated page from the URL -->
+https://<cdn>/dx-maps/<bundle>/<profile>/index.html?list=700
+```
+
+**What you get today:** the DOXA groups that belong to that list. Rows and prayer data come from the
+DOXA API, so a list's groups that DOXA does not carry are not shown yet. An unknown list falls back to
+`doxa` with a console warning. If a list's membership file cannot load, the map shows **no**
+groups rather than DOXA's whole list under the wrong name. Composites pass `list` to every child.
+The definitions live in `library/lists/lists.json`; `bun run lists` regenerates the membership files.
+Full contract: [reference-universal-props.md](./reference-universal-props.md), section 5.
+
+---
+
+## Hide the Plugin Studio header
+
+The Studio header is where you set the universal props (language, engine, token). **Hide header**
+collapses it so the plugin takes the full height; a **Show header** button stays in the top corner
+to bring it back. The choice is remembered in this browser.
+
+---
+
 ## Embed under a strict Content-Security-Policy
 
 No bundle needs `'unsafe-eval'` (translations compile without `eval`; `bun run check:no-eval`), and