Sweep or vacuum your floors thoroughly to remove dirt and debris. Remove any stuck-on adhesive or other substances from the floor with a metal scraper.
Find the center of the room by measuring along each wall to find its center point. Snap a chalk line across the room at each center point to create a large T in the center of the room. Starting the tiles at the center of the room will prevent all of the cut carpet tiles from ending up on one side of the room.
Peel the paper from the first carpet tile, exposing the adhesive backing. Place the tile at one of the corners of the T in center of the room. Press it firmly into place.
Set tiles all around the first tile. Peel off their backing paper and press the tiles closely together to minimize the seams. Continue setting tiles, working out toward the edge of the room. Set all the whole tiles that will fit on the floor.
Measure the edges of the room where tiles will need to be cut to fit, using a tape measure. Mark the back of each tile where it will be cut. Set a straightedge along the mark and cut along it with a utility knife. Peel off the backing paper and set the tile in its place on the floor. Continue cutting, peeling and placing the tiles until the floor is completed.