Use tile nippers or a hole saw designed for tile to cut curves.
How to cut tile on shower wall.
Cut away large sections or large cutouts with a handheld circular saw equipped with a tile cutting stone blade.
Start at one end of the cut line and run the blade along the tile surface to the other end.
Periodically check the tile line with a level to be sure they are straight.
Set the depth of the blade to 1 4 inch.
Use a tile cutter to just score the length of the tile and press firmly to cut.
Make multiple passes with the blade if needed to cut through the tile and to the subsurface.
Cut through the tile using an angle grinder.
Use bullnose for exposed edges or you can use trim pieces.
Use spacers between the tile to make sure the gaps are consistent.
Cut as needed with tile snips or a wet saw to allow tile pieces a better fit around shower faucets and shower heads.
Or you can use a 4 1 2 angle grinder with a tile blade.
This tends to happen when homeowners need to cut a large hole in tile.
For exposed edges set edge trim or bullnose tile pieces in place.
You can buy a 3 or 4 carbide hole saw but they are super expensive.
Spray water onto the tile when needed to keep the surface wet.
Once only the bottom row is remaining remove the support board.
Getting stuck and not having an answer well that s my biggest fear.
If your shower pan is not level then the level line you created to mark the top of the first row will mean that some of your tiles need to be cut.