Adapt readme

Signed-off-by: Tushar Goel <tushar.goel.dav@gmail.com>

Author: TG1999

etc/scripts/d2d/README.rst

@@ -73,3 +73,20 @@ Dependencies
 * Bash
 * Docker
 * Local filesystem permissions for creating ``./d2d`` and writing output
+
+
+Before running the script:
+----------------------------------
+
+Ensure the script has execute permissions:
+
+.. code-block:: bash
+
+      sudo su -
+      chmod +x run_d2d.sh
+
+Then execute:
+
+.. code-block:: bash
+
+      ./run_d2d.sh ...