Each level starts with one block standing tall amongst the others. To move it, just use the direction keys on your keyboard. The block will tip on its side or stand up, depending on which way you move it. You want to move it to the block on the map that is rising and sinking. However, you have to be careful where you roll your block. If it falls off the side of the blocks, it blows up. If it lands on an unstable support, it can fall through. Look for teleportation squares, which will help you get closer to your goal square.