Install the wall tile in a pyramid shape.
Tiling out of plumb walls.
If this is the case you could remove the first course of tile and cut the board above the flange punch the board in and screw it.
Do you stack the tile.
If this is not the case then forget i brought it up.
Find the midline of the wall from ceiling to floor and mark it with a chalk line.
Check your floor for level and walls.
A batten board helps you start your bottom most course or row of tiles.
How do we deal with that doing tile.
You will lay out your first tile directly on this line and your.
Tips for tiling a wall 1.
I hesitate to bring this point up but i think guess your walls are out of plumb because you capped the metal upturn flange of the tub with the cement board.
Hang a batten board to prevent tile slippage.
So you ve got that bottom row of tile.
How to deal with out of plumb walls for tile.