Thanks for playing! We apologize for the lack of guidance in the game. Essentially, the bag moves as if it's being blown by the wind. Press 'D' for wind from the right, which pushes the bag left, and 'A' for wind from the left, which pushes it right. 'W' moves the bag forward and 'S' moves it back, based on the camera's direction. The movement is physics-based. Btw, the ground is completely safe—you might find it easier to roll on the ground.
We intentionally didn't provide precise control because it would be unrealistic for a bag to drift precisely in the sky.
Thanks for your feedback and for playing!