The definitive style implied for the subway tiles can be a variety of designs that can be incorporated in modern bathrooms with different shapes and patterns. The tiles can form rectangle shapes or even octagons.
Start by covering the entire wall with stripes made out of rows of white tiles and black tiles. Every time a new wall is started, the opposite color must be used first to create diversity and also to extend the row patterns to the bathtub or shower; the same pattern can be followed from the walls or you can opt to extend the pattern to the bathroom vanity if it accommodates well enough.
Black and white subway tiles can be used for creating octagon shapes; also, to add a little diversity, white octagons with black backgrounds and vice-versa, or you can opt to create octagons in the corners only and develop a nice creative tilling that will inspire a mosaic look on the bathroom walls.
Squares can be created on bathroom walls in horizontal pattern with white backgrounds, or the other way around, making them smaller or larger depending on the preference, and even alternate between the sizes for a different outcome. Creating white squares on a black tile wall or placing black tiles in the center of a white tiled wall can give a complex look to the bathroom. The squares can be used to create the frame of a mirror and attached with a strong adhesive substance.
Mount black and white subway tiles randomly on the wall to create an abstract and non-symmetrical look, or make different patterns by placing two black tiles in a row followed by three white one. “X” style shapes can be formed on the walls, and also stars and triangles, varying in sizes and shapes so that a mosaic pattern will cover the entire wall.