add instructions for game deployment

Author: hectorsector

README.md

@@ -2,7 +2,12 @@
 
 A project based learning activity for people who are getting started with Git and GitHub.
 
-You can play the game at: https://githubschool.github.io/github-games/
+To play the game:
+1. Go to the **Settings** tab of this repository.
+1. Scroll down to the section titled _GitHub Pages_
+1. Select **Master** from the Source drop-down.
+1. Click **Save**.
+1. Navigate to the URL provided in the same section.
 
 >> _*SUPPORTED BROWSERS*: Chrome, Firefox, Safari, Opera and IE9+_