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+# How to document your extension
+
+So you've written an [extension](/extensions/basics). Awesome! Now you want to add some documentation to help people use it. Great! Maybe you even want some docs for other *developers* working on it too. Very good. This page will help you set up your own documentation *book* (just like this Developer Guide) for your extension.
+
+!!! summary "Example"
+    For a fully-featured working example of extensions documentation, look at CiviVolunteer.
+
+    * Read the published [CiviVolunteer book](https://docs.civicrm.org/volunteer/en/latest/)
+    * Inspect the following source code to see how it's made:
+        * [`/docs/`](https://github.com/civicrm/org.civicrm.volunteer/tree/master/docs) within the project repo (to store all the content in markdown files)
+        * [`/mkdocs.yml`](https://github.com/civicrm/org.civicrm.volunteer/blob/master/mkdocs.yml) within the project repo (to specify book structure)
+        * [`/books/volunteer.yml`](https://github.com/civicrm/civicrm-docs/blob/master/books/volunteer.yml) within the `civicrm-docs` repo (to specify how the book is to be published)
+
+
+## Overview
+
+Basically how this works is:
+
+1. You use the git repo for your extension to store its documentation.
+* You store the content in [markdown](/markdownrules) files within a `docs` directory in your project.
+* You use git branches just like you normally would, with that `docs` directory sitting there in every branch.
+* You put one file at the root level of your poject, `mkdocs.yml` to configure some of the high-level details of your book.
+* You use MkDocs locally to preview your book.
+* When you're ready, you make a pull request on our [publishing system](https://github.com/civicrm/civicrm-docs) to add the necessary configuration for your book, so that it gets published to [docs.civicrm.org](https://docs.civicrm.org).
+* You configure GitHub to tell our publishing system when to publish updates to your book.
+
+Follow along in the steps below to get a book up and running for your extension.
+
+## Set up `mkdocs.yml` {:#config}
+
+Create a new file called `mkdocs.yml` in the root level of your project with the following content:
+
+```yaml
+site_name: Your Extension Name
+repo_url: https://github.com/yourusername/org.civicrm.yourproject
+theme: material
+
+pages:
+- Home: index.md
+
+markdown_extensions:
+  - attr_list
+  - admonition
+  - def_list
+  - codehilite
+  - toc(permalink=true)
+  - pymdownx.superfences
+  - pymdownx.inlinehilite
+  - pymdownx.tilde
+  - pymdownx.betterem
+  - pymdownx.mark
+```
+
+Replace values on the first two lines with your own. Leave everything else as-is (for now).
+
+
+## Add content
+
+1. Add a `docs` directory at the root of your project.
+2. Within that, add a `index.md` page, and put some [markdown](/markdownrules) content in it.
+
+Now you should be able to run `mkdocs serve` from within your project directory to start previewing your content. See [instructions here](/documentation/#editing-locally-with-mkdocs) to get MkDocs set up.
+
+You can add more pages by creating more markdown files and specifying these files under `pages` in `mkdocs.yml`.
+
+!!! note
+    We have [markdown code standards](/markdownrules/#standards) and a documentation [style guide](/best-practices/documentation-style-guide/). Adherence to these rules within your extensions docs is recommended but not required.
+
+
+## Submit your book to our publishing system {:#submit}
+
+Once your book is in good shape it's time to get it up on [docs.civicrm.org](https://docs.civicrm.org).
+
+1. Go to the [books configuration within our publishing system](https://github.com/civicrm/civicrm-docs/tree/master/books)
+1. Click **Create new file** to begin adding a config file for *your* book.
+1. For the file name, use something like `foobar.yml`, where "foobar" is your extension's **short name**. This is the name that will be used in the URL for your docs.
+1. Copy paste the following content into the file editor:
+
+    ```
+    name: Foo Bar
+    languages:
+      en:
+        repo: 'https://github.com/username/org.civicrm.foobar'
+    ```
+
+    * There are lots of other settings you can put here if you want to have multiple languages or versions. Look at `user.yml` as an example of a book (the User Guide) which takes advantage of all the possible settings.
+    * But if you want to keep it simple and just have one English edition which points to the `master` branch of your repo, then stick with the above settings.
+
+1. Adjust `name` and `repo` to your own values
+
+    * The `name` you set here will be shown in the list of all books on [docs.civicrm.org](https://docs.civicrm.org) as well as at the top of every page of your book. Use whatever **long name** you've chosen for your extension, such as "Foo Bar", or "CiviFoobar". (*Don't* use a fully qualified name like "org.civicrm.foobar" because that wouldn't look so nice to visitors.)
+
+1. Click **Propose new file**.
+1. On the next screen, click **Create pull request**. (You're not done until you create a pull request!)
+
+At some point (hopefully soon!) someone will merge your PR and get the necessary config for your book up on the server. Then it can be published.
+
+## Manually publishing your book {:#manual-publishing}
+
+Once your book's config is up, you can go to the following URL to ask the publishing system to publish (or re-publish) your book:
+
+    https://docs.civicrm.org/admin/publish/foobar
+
+(where `foobar` is the short name you used for your book)
+
+Publishing your book manually is fine at first, but once you update the book later, you might wish to avoid this extra step. This is why we have automatic publishing...
+
+## Automatic publishing
+
+*(Currently only possible if your repo is on GitHub.)*
+
+When you set up automatic publishing, GitHub will tell the publishing system when content within your repo has changed, and the publishing system will re-publish your book as necessary.
+
+1. Go to your repo on GitHub.
+1. Go to the **Settings** tab at the far right.
+1. Go to **Webhooks > Add webhook**.
+1. Set the **Payload URL** to `https://docs.civicrm.org/admin/listen`
+1. Set the **Content type** to `application/json`
+1. Set **Which events would you like to trigger this webhook?** to 'Let me select individual events' and select 'Pull request' and 'Push' (since these are the only events that should trigger an update)
+
+Now when you make changes to your docs, those changes will be published automatically *and* you'll receive an email notification from the publishing system informing you of the status (including any errors) of the publishing process.
diff --git a/mkdocs.yml b/mkdocs.yml
index 1cbe00374977ef06ecaabb90e83c5d13ae663625..1e0147a96b705ded1493f5caf5b889d38471128e 100644
--- a/mkdocs.yml
+++ b/mkdocs.yml
@@ -195,6 +195,7 @@ pages:
     - hook_civirules_logger: hooks/hook_civirules_logger.md
 - Documentation:
   - Writing Documentation: documentation.md     # page-tree = NEED_PAGE_MOVE to /documentation/writing.md
+  - Documenting Extensions: documentation/extensions.md
   - Markdown: markdownrules.md                  # page-tree = NEED_PAGE_MOVE to /documentation/markdown.md
   - Style Guide: best-practices/documentation-style-guide.md  # page-tree = NEED_PAGE_MOVE to /documentation/style-guide.md
 - Content to reorganize: