Wall tiles that go from floor to ceiling and end to end don't need to be edged, but if the tiled area stops at mid-wall, a border is needed, since standard tiles have unfinished edges. One solution is to line up edging tile (or ``bullnose'' tile) along the border of the tiled area. The tiles are finished on one edge so they can sit along an open wall.
Measure the length of the tiled area along which the edge tiles will be set. Mark the middle of the length.
Spread tile mastic onto the back of an edge tile using a notched tiling trowel.
Press the edge tile against the wall, next to the tile area, at one side of the middle mark. Set the tile with the finished (``bullnose'') edge facing away from the tiled area and sitting flush against the open wall. Put spacers between the edge tile and regular tiles.
Apply mastic to the second edge tile. Press it to the wall next to the first edge tile, again positioning it so the finished side faces away from the tiled area. Repeat for the rest of the edge tiles, lining them up along the tiled area. Cut the edge tiles at both ends on a tile cutter to fit. Let the mastic set 12 hours.
Pull out the spacers. Grout the edge tiles, using a grout float to press the grout into the gaps between the tiles.
Allow the grout to stay in the lines for 10 minutes. Wipe up the excess grout from the surface of the tiles with a damp sponge, leaving it in the lines while smoothing it out.