The lower is a bathroom, the harder it is to decide how to furnish.
Some tips that will help you: If you want to visually expands a small bathroom choose tiles with rectangular tiles in horizontal stripes. Stripes create the illusion of visual enlarging space and the room will seem more spacious.
Another trick would be open and bright colors. Regardless of the chosen material try to avoid dark colors which darken the room. For more light in the bathroom you can combine white, cream and butter color and light tones of gray or solar yellow.
Even if privacy is one of the first words that come in our minds when hearing the word bathroom, a frosted glass door creates a visual illusion enlarge the room. Another tip is the large mirrors. And they all help to the visual effect. No hiding hygiene products because it is still a bathroom. Comb and toothbrush should not be hidden; actually they can be exploited: a comb-shaped shell, toothbrushes in a bowl-shaped fish or a support you are decorated with shell and pebbles.
A corner bath or a shower will help you to save enough space. However, most would hardly give up with tub and choose shower. Nothing beats a hot bath in the tub after a long day at work.