Has he laid it out on the floor or a table first??

That should happen before any attempt at wall placement

This! Thank you SO MUCH.

steph, a herringbone layout should have a tile that is length divisible by its width. 3x9 2x8, would have been better.

the tilers have to use a speed square to get the 45 on the end of the tile, and then have to starting lines like dragonfly showed you. it's hard to type out the explanation

here's my floor and how we started it

same two lines shown below

find center on your wall, but you don't just lay the tile on the line. find the two points on the tile by taping off a 45 using the square. see the red lines in the pic? the right one is the tile point, the left one w/the horiz. line comes from finding the 45 on that end portion.

you should perfect symmetry on both ends if it's done correctly. see the cut pieces on the outer edges? both sides should be the same. make sure he does a dry layout on the floor first

and you certainly don't want this

I leave this to the tile experts. Would it be easier if the tile were done at a vertical application?

Is this any easier?? Obviously only if the OP likes it....