Add information in README

packages/create-astro/README.md

@@ -43,4 +43,19 @@ May be provided in place of prompts
 | `--template` | Specify the template name ([list][examples])        |
 | `--commit`   | Specify a specific Git commit or branch to use from this repo (by default, `main` branch of this repo will be used) |
 
+### Debugging
+
+To debug `create-astro`, you can use the `--verbose` flag which will log the output of degit and some more information about the command, this can be useful when you encounter an error and want to report it.
+
+```bash
+# npm 6.x
+npm init astro my-astro-project --verbose
+
+# npm 7+, extra double-dash is needed:
+npm init astro my-astro-project -- --verbose
+
+# yarn
+yarn create astro my-astro-project --verbose
+```
+
 [examples]: https://github.com/withastro/astro/tree/main/examples