📖 Update README.md with myst instructions

Author: rowanc1

README.md

@@ -2,6 +2,14 @@
 
 Documentation for authors submitted Notebook based publications via Notebooks Now!
 
+https://agu-submission.curve.space/
+
 ## Contributing
 
-This documentation is open to contributions from the wider community. Contribute by opening and issue or PR with changes or additions.
+This documentation is open to contributions from the wider community. Contribute by opening and issue or PR with changes or additions. To run this website locally follow the instructions on https://mystmd.org to install `mystmd`, then run:
+
+```bash
+myst start
+```
+
+See [guide on MyST Markdown](https://mystmd.org/guide/quickstart-myst-markdown) for help on syntax. Any changes you make to the content will be automatically updated and when merged to main [deployed here](https://agu-submission.curve.space/).