The small modern bathroom is the easiest thing you can probably design. Why is that? Because it's not fussy, it's clean lines, and there's some elements that are pretty key. One is the vanity. You want to make sure that functionality, it all functions well. So you have your vanity, you can do it in a really dark wood finish as an accent, or you can go kind of Scandinavian and floating and very airy, and do a lighter wood with just the vessel sink.
Make sure that everything recedes, so you have your mirror and your light fixtures that are really sleek and modern, maybe they're recessed into the wall, if you have space there or they have a clean wood trim around the mirror. You don't want too many things protruding out.
Your tile work, bigger is better in the modern world when it comes to tile, because it makes the space feel bigger especially a small bathroom. So the bigger floor on the floor and then maybe a nice accent wall tile. What's great in a modern bathroom is that a nice clean look is when you bring the tile up to the halfway point or you even go a step above that and you bring it all the way to the ceiling.
By doing the whole bathroom in tile, you would think that it feels very strict and straight, but it really doesn't. It makes the space feel bigger. It's easy to maintain and not only that, it makes it look really clean and modern. Those simple elements, maybe you throw up a nice shower curtain, or if you can splurge a little bit get a glass enclosure. Your bathroom, you can't lose when you're going modern.