Add instructions how to run ingestion script from command line

documentation/catalog/guides/adding_a_new_provider.md

@@ -97,6 +97,19 @@ in the
 as well as a corresponding test file. Complete the TODOs detailed in the
 generated files to implement behavior specific to your API.
 
+You can run the provider script directly from the command line to run the
+ingestion outside of the workflow. The TSV file will be saved in your /tmp/tmp
+folder.
+
+- First make sure that the directory with the scripts is in your PYTHONPATH
+  ```
+  export PYTHONPATH=<path_to_openverse>/catalog/dags
+  ```
+- Then cd into the Openverse dir and run the script as so:
+  ```
+  python catalog/dags/providers/provider_api_scripts/<your_script>.py
+  ```
+
 Some APIs may not fit perfectly into the established `ProviderDataIngester`
 pattern. For advanced use cases and examples of how to modify the ingestion
 flow, see the