Draw a circle on each floor tile with a pencil compass; make it approximately 4 inches in diameter. You can make the circle in the center of the tile, or closer to the edge. The location doesn’t matter.
Cut along the line of the circle with a jigsaw. Remove the circular piece of tile, referred to as a disc, and set it aside. Cut the remaining two tiles in the same fashion.
Sand the edges of the discs with a piece of fine grit sandpaper. You won’t need a machine for this process; simply fold the sandpaper in half, hold it in your hand, and sand the discs.
Move all furniture away from the piano. This will give you plenty of room in which to work.
Close the keyboard cover and the piano lid. Ask two helpers to lend a hand; don't attempt to lift the piano yourself.
Instruct your helpers to raise the piano, one leg at a time, a few inches above the floor. As soon as a leg becomes free, position a disc under it and lower the piano. The weight of the piano will keep the disc in place and protect the floor from dents.