The specifics of bathroom window curtains is that you pick window treatments for a pretty small room with a rather high humidity. Thus be careful with the curtains fabric and patterns. Say “no” for all large prints even if you love them. A large print in a small bathroom will “eat” all the attention.
The classic choice of the window curtains for bathroom is solid window treatments in pastel colors. The curtains can be washed in a washing machine. Do not choose too long curtains. The floor in any bathroom is often wet, thus your curtains will be wet as well. Never pick too dark bathroom curtains for windows, even if you keep in your mind you work at a gothic interior design. Even in this case the curtains should be lighter than the walls and the rug. The choice depends on the style you have already chosen for this room.
In some cases, for example in a coastal style bathroom, the fishing nets may replace the curtains and become a very specific bold decor. French provence bathrooms will look lovely with cute light cotton curtains with small patterns.
Marine style of your bathroom will influence the choice of the curtains. Pick navy blue curtains with small white gulls or sky blue and light green window treatments. Some DIY variants of the curtains offer making small embroidery on usual sheets .