This game is pretty straight-forward. You click on the matching nova’s as fast you can. Make sure they match by checking the outline or border of the nova. Some of them can be tricky.
Tips: If your opponent clicks on a nova first, then you won’t be able to click it. So speed is important.
Since we naturally read from left to right, top to bottom, my suggestion is to start near the bottom. You have a better chance of getting those nova’s first.