Update README.md

Author: valsdav

README.md

@@ -101,6 +101,13 @@ After making changes, make sure to run test cases and linting checks.
 - Original source hosted at [GitHub](https://github.com/cms-cat/order)
 - Report issues, questions, feature requests on [GitHub Issues](https://github.com/cms-cat/order/issues)
 
+Setup the environment:
+```shell
+export ORDER_CLEAR_CACHE=True                                          
+export ORDER_DATA_LOCATION='/path/to/order-data'
+export X509_USER_PROXY=your-cert-file
+```
+
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