Tiling around a toilet might sound like a complicated and intimidating part of your bathroom tiling project, but in fact it's a lot easier than it looks. The toilet base completely covers the joint between the tile and the toilet drain, so the cuts don't have to be perfect. This allows you to use tile nippers to make the cuts. They look like pliers with flat claws at the end, to "bite'' away chunks of tile and gradually shape the curve you need to go around the drain.
Remove the toilet by turning off the water source, disconnecting the water line and unscrewing the two mounting bolts on the base, loosening them with pliers. Pull the toilet straight up and move it out of the room.
Use a chalk snap line to divide the floor into four sections, with two lines that intersect in the middle of the room.
Install tiles starting at the intersection, spreading thinset mortar with a mortar trowel and setting the tiles in place at the lines. Build out toward the walls, putting spacers between the tiles and using your tile cutter to cut the tiles as needed to fit at the walls. Install full tiles around the drain as close as they will fit without cutting, so there's a square perimeter around the drain. Let the tiles dry overnight.
Lay full tiles to fill up the square perimeter around the toilet drain, setting them over the hole as if there's no drain there. Space the tiles as the rest of them are spaced, so you can see the edge of the drain in the spaces.
Trace the shape of the toilet drain onto the tops of the tiles with your pencil. Make the lines about 1/4 inch outside the drain.
Take up the tiles. Use your nippers to bite away small chunks of each tile, working your way toward the curved line, then trimming the tile right up to it. The edge will be jagged, but the toilet base will cover it up.
Set the tiles in mortar around the toilet drain, leaving about 1/4 inch of space at the edge of the drain. Let the mortar set. Pull out the spacers and grout the whole floor, spreading the grout over the surface with a grout float, pressing it into the lines between the tiles. Wipe up the excess grout with a damp sponge. Allow the grout to dry, and replace the toilet.
Wear goggles when using your tile nippers.