Opt to cut sheets of “Ditra” membrane to fit the area you are tiling. You will need to apply thinset to the concrete and smooth the membrane sheets down with a trowel. You can also paint a thick coat of liquid anti-fracture membrane on the concrete with a roller brush. The anti-fracture membrane keeps an insulated layer between the concrete and the tile so that it can move with the change of seasons and temperature without cracking the tiles. [2] X Research source
Use a wet saw to cut ceramic tile to fit in narrower spaces. You can also cut tiles with a 4-inch angle grinder with a masonry blade in it.
Leave a 1/4" gap on all edges (by walls, cabinets, fireplace hearths, etc. ) to allow for thermal expansion.
Wipe them off immediately to avoid ruining the surface of the tile.
