In message , Jim
writes
Could you not lay the tiles so that the lower side edges just touch each
other and then put a bead of grout along the join and level off to 45
degrees so that it is flush with the top edges?

Hmm, not sure I think that would look that good.

Pro tilers (from what I've seen in my parents and In-laws bathrooms,
usually go for the corner 'beading' route. And I think it looks fine.

When I did it I went the mitring route. I was using one of the electric
tile saws and this makes cutting mitred edges relatively easy. As all
things take your time and you can get a good job. But of course it adds
greatly to the time, and would add inordinately to the cost if paying
for the job.

I went further and 'framed' my window opening. I was using 3 different
coloured tiles and used one to cut rectangular tile pieces used to make
a frame around the window opening. It looks really good.

Of course all this fiddling took ages, compared to the rest of the
tiling, but I'm still impressed with he job when I have a shower :-)
--
Chris French, Leeds