1. Click the “Green flag”. 2. Follow the instructions. 3. In the first round, the player (you) get to play first. In subsequent rounds, the program decides randomly who will go first.
This program implements this popular two-player game. You play against the computer. If you want to understand how I designed this program, please read this article: http://www.abhayjoshi.net/spark/scratch/blog/tic-tac-toe.pdf