Sorry for your bad experience with the minigame. We didn't have the time left for a proper tutorial, and it has performance issues in the web version. We recommend downloading the game for good measure.
Here's a tutorial:
It's a drag-and-drop mechanic. You have two drop-areas: The border with the fishes and Sorcell himself. Your task is to drag the good productive thoughts onto Sorcell and the unproductive thoughts into the border.
Thank you still for trying so hard ;v;