There are many styles and types of tiles. There are even more patterns that can be created with individual sizes, mixed sizes and mixed colors. When using 12- by 24-inch tiles alone, you are limited in the pattern that you can create. Although the pattern is still elegant, there is really only one way of laying the tiles when used alone. This is known as the subway tile effect. You can, however, change the angle of the tiles to create a completely different feel for the room.
Remove any floor molding. Pry the molding from the wall carefully so you don't damage the drywall. If this is a new construction, skip this step.
Clean the floor of any debris, old broken tiles, carpet and glue. You will need to have a bare plywood surface. Inspect the plywood. If it needs to be replaced, do so now.
Measure the room in both directions. Divide the measurement in half. Locate that measurement in the room. Mark the area on the floor where that measurement is located. Do the same with the other direction. You need to mark this measurement twice so that you can create a straight line.
Mark a line connecting the marks on the floor using a chalk line. A chalk line is a piece of string covered in chalk powder. Align one end of the string with one of the marks. Pull enough string out of the roll to be stretched to the other mark. Pull tight. Snap the string by grabbing it at the center and pulling up from the surface approximately six inches. Let the string go. This step will require the help of two other people. Do this with the other direction. You should have created a point in the room where the two lines match up. This point is the center of the room and is also where the first tile will be installed.
Locate the center of the first tile. Mark the back side of the tile.
Place the first tile down over the center mark in the room. Turn the tile in the direction that you want the tile to run. For a straight tile, align the corner of the tile with the two chalk lines on the floor. For a tile with an angle, align the mark on the back of the tile with the center mark of the room. Turn the tile to the angle you wish to use.
Mark the four sides of the tile with a carpenter's pencil. Remove the tile.
Mix the thin set mortar to thick consistency. Only mix the amount you will be able to use in 15 minutes.
Drop a glob of thin set approximately the size of a softball in the trace marks on the floor. Move the thin set to cover the inside of this mark with a trowel. The grooves on the trowel will leave "trenches" in the thin set. Face the trowel lines in the same direction. Avoid covering the lines completely, as you will need to find the line to place the tile.
Align the first tile with the marks on the floor. Set it in place and wiggle the tile gently into the thin set. Do not push the tile into the grout.
Place a level on top of the tile. Use a rubber hammer to tap the tile gently on the higher spots on the tile until it sits level.
Apply more thin set next to the first tile. Place the second tile in the same manner as the first. Insert two tile spacers between each tile. This will ensure an even grout space between the tiles.
Finish the first row of tiles. You will need to cut a tile to fit the last space next to the wall. Measure and mark the tile where a cut needs to be made. Line up the speed square, a metal triangle used for measuring, with the marks. Trace along the flat edge of the speed square with the carbide pencil, which will cut into the tile. Press firmly. Score the tile a few times. Grab the side of the tile that you don't need with a pair of nippers. Grip the nippers and the tile tight with your hand. Bend the tile until it snaps in two. Sand the cut part of the tile with a two-sided grit rubbing stone. If you are tiling a large room, you may want to rent a large score-and-snap machine.
Center the first tile of the second row between two tiles. Mark the center spot on the floor or on the two tiles of the row before. Install this tile the same way you did the others. Finish the room staggering each tile between the two tiles of the previous row. Do not walk on the tiles or put any pressure on them of any kind. Let the tiles sit for an entire day before applying the grout.
Remove the tile spacers. Mix the gout to a thick consistency. Drop the grout over the space between each tile. Don't worry about getting the grout on the tiles, it will wash off. Use a rubber float to spread the grout over the entire floor surface. Work the grout into the spaces between the tiles as you go.
Remove the excess grout from the tiles with a damp sponge. Be sure to remove all excess grout. Let the floor sit untouched for a full day.
Mop the floor. You may need to do this a few times before all of the grout residue is gone.
Apply a silicone sealer to the floor after one week.