Update README

README.md

@@ -28,6 +28,9 @@ Use the included Compose file to start the required services to serve the projec
 Prerequisites:
 
 1. Docker image is built (see above).
+1. A local `ports.conf` and `default.conf` should be generated to configure Apache within
+   the running container (examples are in the `kustomize\overlays` directory). These
+   files will be bind-mounted in the container.
 1. A local `settings.php` should be generated containing site configuration that will be
    bind-mounted at `web/sites/default/settings.php`.
 1. Local `.env.mysql` and `.env.flatbacks` files should be created, containing secrets.