Put on safety goggles and gloves. Removing tiles is dusty work, and tile shards can cut, so take precautions before you begin. Cover adjacent areas with drop cloths to protect them from dust.
Position the tip of a nail in the center of the first tile to be removed and hit it with the hammer. This will break the tile away from the substrate below it without harming the substrate.
Hold the chisel at a 45-degree angle to the tile and hit the end of the chisel with the hammer, pushing the chisel into and under the tile. Continue to gently chisel the tile away from the concrete until you've cleared a space at least 12 inches in width down to the concrete.
Position the end of the pry bar beneath the edge of the tiles next to the cleared space. Apply pressure to the pry bar to pull the tiles and adhesive off of the concrete. Continue to pull up the tiles in this manner, when you encounter a tile that is stuck, break it free with the hammer and chisel.
Scrape the concrete with the 6-inch razor blade to remove any remaining adhesive and to prepare the area to accept fresh tile.