Place a peel n' stick tile directly on top of a full tile closet to the wall. Do not peel away the adhesive backing.
Put another tile, without the backing removed, on top of the other tile. Position it against the wall. Make sure the tile is positioned so that the pattern or grain will run the correct way once installed.
Make a pencil line by running a pencil lead against the edge of the top tile, while marking on the loose bottom tile underneath. Remove both tiles.
Cut along the pencil line with a pair of scissors or place a straight edge on the pencil line and score the line with a utility knife. Score it until you cut all the way through the tile.