Click the green flag. When you do that, the character will either raises his shield or his sword. If he raises his shield, click the left arrow. If he raised his sword, click the right arrow.
This is just the start of a bigger game. I'm trying to basically re-make Swords and Souls, but different. So this is one minigame. And I'm probably adding more to this. I have a menu, another minigame, and the actually battles left to do.