update README: how to play

Author: HilmiZul

README.md

@@ -9,6 +9,10 @@ Morning Exercise is a cool game made by ml5.js using handPose. I created this ga
 - Open `index.html` with your lovely web browser
 - Allow camera
 
+# How to play?
+
+Angkat kedua tangan, collide-kan keypoin masing-masing pergelangan tangan dengan obstacle. Pokoknya gerakkan tangan dan badanmu! 😂
+
 # Changelog
 **5 April 2025**
 - Update libraries