Merge pull request #157 from NASA-NAVO/jlab-startdir

Add starting directory instructions for Jupyterlab

00_SETUP.md

@@ -131,12 +131,24 @@ python check_env.py
 ```
 
 ## 7. Starting Jupyterlab
-From the directory containing the notebooks:
+
+From the top-level directory of the repository, change directory to the
+`content/` subdirectory:
+
+```console
+cd content
+```
+
+Start Jupyterlab from this subdirectory:
 
 ```console
 jupyter lab
 ```
 
+You can then use the Jupyterlab file browser to navigate to the
+`reference_notebooks` and `use_case_notebooks` subdirectories that contain
+the notebooks.
+
 ## 8. Handling Notebooks in MyST-Markdown format
 
 The Jupyter notebooks in this repository are in