Create a focal point in the floor by designing a shape in the center and using uniform tiles around it. For example, design a sundial shape for the center of the room and use a neutral tile around it so they don't draw attention away from the focal point.
Lay a checkerboard pattern on the floor. This was often seen in 1950s diners. You can use large black-and-white tiles or try adding color, such as red and white, to the look. By turning the tiles at an angle, you can create a diamond-shaped checkerboard for even more interest. This design is usually seen in kitchens.
Use two different sized tiles to form a pattern. Try laying a large square next to a large rectangle of equal height. Or a large square next to two smaller rectangles that form the same sized square when laid together. The two tile sizes can also be in different shapes, such as triangles laid with squares.
Create a border with tile of one color and fill the room with tile of another color. For example, use a black square border along the outside of the room and fill the middle of the room with white tile. Or lay three rows of large tiles and fill the fourth row with smaller, colorful tiles. Lay the border tiles in a different pattern or shape, such as diamonds, so they stand out even more.