Document package extensions (#43)

extensions/creating-extensions.md

@@ -91,18 +91,6 @@ the config file can be loaded as a CommonJS or ESM file.
 
 :::
 
-## Deploying your Extension
-
-To deploy your extension, you have to move the output from the `dist/` folder into your project's
-`./extensions/<extension-folder>/<extension-name>/` folder. `<extension-folder>` has to be replaced by the extension
-type in plural form (e.g. interfaces). `<extension-name>` should be replaced with the name of your extension.
-
-::: warning Configurable Folders
-
-The path to the built extension as well as the extensions directory are configurable and may be located elsewhere.
-
-:::
-
 ## Developing your Extension
 
 To learn more about developing extensions of a specific type, you can refer to one of the individual guides:
@@ -127,3 +115,45 @@ When working on extensions, try setting the
 on changes automatically.
 
 :::
+
+## Publishing your Extension
+
+To make an extension available to all Directus users, you can publish the npm package created by
+`@directus/extensions-sdk` to the npm registry. Make sure the name of the package follows the naming convention for
+package extensions: `directus-extension-<extension-name>` or `@<scope>/directus-extension-<extension-name>`.
+`<extension-name>` has to be replaced with the name of your extension.
+
+## Installing an Extension
+
+There are two ways to install an extension.
+
+### Package Extension
+
+Package extensions are essentially npm packages. They can be installed from the npm registry, from a tarball, from a git
+repository or any other means supported by npm. On startup, Directus will automatically load any package extension
+installed into your Directus project folder.
+
+To install an extension from the npm registry, simply use the npm CLI:
+
+```bash
+cd <directus-project-folder>
+npm install <full-package-extension-name>
+```
+
+`<project-folder>` has to be replaced by the Directus project folder. `<full-package-extension-name>` should be replaced
+with the full name of the package extension (e.g. `directus-extension-custom`).
+
+### Local Extension
+
+Local extensions are essentially the files generated by the `directus-extension build` command. They can be installed by
+copying those files into a specific extensions folder.
+
+To install an extension locally, you have to move the output from the `dist/` folder into your project's
+`./extensions/<extension-folder>/<extension-name>/` folder. `<extension-folder>` has to be replaced by the extension
+type in plural form (e.g. interfaces). `<extension-name>` should be replaced with the name of your extension.
+
+::: warning Configurable Folders
+
+The path to the built extension as well as the extensions directory are configurable and may be located elsewhere.
+
+:::