CMSNAV-798: Add further guidance for using the get_token command

Author: tomhosker-bjss

README.md

@@ -38,6 +38,13 @@ Consider using a **dev container**. While this is in no way a requirement, you m
     - You can get an `APIGEE_ACCESS_TOKEN` via the `get_token` command. If you don't already have access to the `get_token` command, you can install it using [these instructions](https://docs.apigee.com/api-platform/system-administration/auth-tools#install).
     - You can get the latest `SOURCE_COMMIT_ID` via the `/_ping` endpoint of the proxy you're using. For example, with `PROXY_NAME` set to `nhs-website-content-api-internal-dev`, we would want to access the URL https://internal-dev.api.service.nhs.uk/nhs-website-content/_ping - this should return some JSON, and the value we want has key `commitId`.
 
+:bulb: One way to use the `get_token` command is to call:
+
+```
+export APIGEE_ACCESS_TOKEN=$(SSO_LOGIN_URL=https://login.apigee.com get_token)
+echo $APIGEE_ACCESS_TOKEN
+```
+
 ### Let's Roll
 
 1. Install by running `make install` from this directory.