It is important to run thinset in the same direction on back of tile and cement board to prevent air pockets when setting large tile. I used a 1/4"x1/4"x1/4" trowel to set these approx. 2'x4' tile.
An example of how not to set tile is provided. Water should always be able to runoff to the drain. The stainless steel edge profile actually acts as a water dam in the example provided.
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