Each day a different pavement is laid, the same for everyone. Its tiles have been disturbed: some turned, some moved.
Lift and lay. Tap a tile to take it into your hand, turn it there if it needs turning, and tap a place to lay it. Laying it on another tile exchanges the two.
Read the seams. Where two tiles agree, the join closes and both grow clearer. A tile agreeing on every side takes its glaze. Dark seams still disagree.
Two kinds of tile. Patterned tiles are turned and matched by their edges. Plain and field tiles (chequers, fleurs, crosses, rosettes, stars) look the same whichever way they face, so only their place matters: follow the repeat.
Bedded fast. A tile with a small iron stain at its foot has never moved. Build around it.
The floor is whole when every seam agrees. There is one floor a day; the next is laid at midnight.