How do you choose ceramic tile?
First, check that it's made for where you want it. Plenty of ceramic tile is wall tile only, and a floor needs one its maker rates for floors.
Then let the glaze and the shape lead. Gloss bounces light around and brightens a small bathroom; satin and matte are softer; crackle and handmade looks give a wall depth and a little irregularity on purpose. Subway, square, hexagon, picket and arabesque each set a rhythm before color does.
Choose the grout with the tile, not after. A matching grout keeps a wall calm; a contrasting one draws every joint, which can be the whole point. And ask about trim: many ceramic lines come with matching edges and corners.