[NDR-318] Update README

Author: jameslinnell

README.md

@@ -31,6 +31,15 @@ The following tools are required for all options:
 - [Git](https://git-scm.com/)
 - Docker (e.g. via [Brew](https://formulae.brew.sh/formula/docker))
 
+Setup an environment variable on your local system. The environment variable points to your national-document-repository-infrastructure directory on your local system.
+For Linux/MacOS users add the following to your ~/.zshrc or ~/.bashrc file
+
+```bash
+export NDRI_LOCATION=<national-document-repository-infrastructure FOLDER location>
+```
+
+For Windows users, please follow Microsoft's recommendations for creating persistent environment variables
+
 ### Method 1 - Dev container within VS Code (recommended)
 
 > [!IMPORTANT]
@@ -70,6 +79,14 @@ lazygit
 - [Node@24](https://formulae.brew.sh/formula/node@24)
 - [[email protected]](https://formulae.brew.sh/formula/[email protected])
 
+### Initial Setup of the container
+
+1. Configure Github-CLI with
+
+```bash
+gh auth login
+```
+
 ## Monitoring
 
 We have configured AWS CloudWatch to provide alarm notifications whenever one of a number of metrics exceeds its normal