docs: add template-sync tool to the documentation

README.md

@@ -38,6 +38,7 @@ with [FrankenPHP](https://frankenphp.dev) and [Caddy](https://caddyserver.com/)
 6. [TLS Certificates](docs/tls.md)
 7. [Using a Makefile](docs/makefile.md)
 8. [Troubleshooting](docs/troubleshooting.md)
+9. [Updating the template](docs/updating.md)
 
 ## License
 

docs/updating.md

@@ -0,0 +1,15 @@
+# Updating Your Project
+
+To import the changes made to the *Symfony Docker* template into your project, we recommend using
+[*template-sync*](https://github.com/mano-lis/template-sync):
+
+1. Run the script to synchronize your project with the latest version of the skeleton:
+
+    ```console
+    curl -sSL https://raw.githubusercontent.com/mano-lis/template-sync/main/template-sync.sh | sh -s -- https://github.com/dunglas/symfony-docker
+    ```
+
+2. Resolve conflicts, if any
+3. Run `git cherry-pick --continue`
+
+For more advanced options, refer to [the documentation of *template sync*](https://github.com/coopTilleuls/template-sync#template-sync).