Take the chalk snap line, and stretch it across the centre of the floor in one direction. Sketch the line, and then lay the chalk snap line in the opposite direction. Sketch the line yet again. It will divide the floor in four equal parts or squares. Now determine that which of these lines you want to be your length line and which of these will be your width line.
Take your ceramic tile, and measure its length. Divide the measurement to make it in half. Now sketch a second line parallel to your width line.
Spread thin set mortar all over a couple of squares, right over the intersection of the lines that you sketched in the centre of the room. Now install the first two tiles while making sure that their long sides are right along the length line.
Place your next two tiles in the next row, keeping in mind the same technique you used to install the first two tiles. Remember to put spacers between your tiles.
Continue the process until you have installed all the tiles in the room. Cut the end of the tiles with the help of a tile cutter if needed to adjust the tiles in the corners or right beside the walls of the room. Let the tiles set overnight.
Pull out all the tiles spacers, and spread the grout all over the tiles in the room. Now take the grout float, and wipe off the face of the tiles throughout your room. Wipe down the excessive grout with the help of a clean but wet sponge. Wipe all the tiles a couple of times before setting the furniture in the room.