Imagine a long rod. Slide a shorter pipe onto it. You move on the X-axis by sliding the pipe left/right on the rod. Move on the Y-axis by rolling the pipe. Clic

Imagine a long rod. Slide a shorter pipe onto it. You move on the X-axis by sliding the pipe left/right on the rod. Move on the Y-axis by rolling the pipe. Click by pushing the entire contraption down.