Update README.md - How to play!

Author: MahmoudFayed

README.md

@@ -11,4 +11,12 @@ The cards game, Developed using the Ring programming language (http://ring-lang.
 
 (3) Screen Shot
 
-![Cards](https://raw.githubusercontent.com/MahmoudFayed/cards/master/cards_screenshot.png)
+![Cards](https://raw.githubusercontent.com/MahmoudFayed/cards/master/cards_screenshot.png)
+
+# How to play!
+
+* Each player opens his/her hidden cards.
+
+* When your card is similar to another card, you get scores.
+
+* If your card is (5) you get scores based on all of the opened cards