README update - vagrant plugin installation

README.md

@@ -69,7 +69,11 @@ using the following convention:
 
 #### Creating a deployment for a test
 
-To set up a simualtion of the adaptive streaming use case scenario 
+To set up a simulation of the adaptive streaming use case scenario first install the vagrant-disksize plugin (if not already installed)
+
+`vagrant plugin install vagrant-disksize`
+
+and then execute the following command
 
 `vagrant --fixture=streaming-sim -- up`