The term Powder Bathroom came from the time when women would say "I am going to powder my nose" instead of going to the restroom. It was more delicate terminology and much more formal. Whether you call it the Powder Room, Restroom, 1/2 Bath, Guest Bath, the bathroom you have designated for guests to use is important and here are some tips to help make it inviting before your guests arrive.
TIP 1: Don't be afraid to make this room DARK. It is already a small space (typically) and it won't get smaller due to a dark color on the walls, so HAVE FUN! Use a bold pattern wallpaper, use a color you would be afraid to use in a large space and make a statement.
TIP 2: Make sure to provide soap, enough toilet paper, and give your guests a hand towel, or better yet, nice disposable paper towels for them to dry their hands.
TIP 3: Lighting---the lighting needs to be good enough to see, but you can have fun in this space since it is typically only used for a quick glance in the mirror, unless your Guest Bathroom doubles as a main bathroom used daily. Add sconces that bring in light and style or perhaps a fun chandelier overhead.
TIP 4: Use an interesting cabinet or sink to show some personality, that can be modern, funky, traditional, but think outside the box.
TIP 5: Think about different shape options on the mirror. Create a focal point by playing up the wow factor on the mirror.