Let's start with fixtures. The standard tub is about sixty inches by thirty-two inches. If yours is larger than that, you may want to consider replacing it. Installing a lower-walled bathtub is also helpful because it will give the illusion of more space.
Pedestal and wall-mounted sinks will take up less room and make the room appear larger. In general, the more visible floor space in a room, the more spacious it will feel. You might also consider installing suspended cabinets instead of a standard vanity.
If you are convinced that you need a vanity, consider installing a smaller version. The standard vanity measures about twenty-four inches wide and eighteen to twenty-one inches deep. However, you can get them as small as eighteen inches wide and thirteen inches deep. Make sure your sink lies flush with the counter because this will also help make the room seem larger. In addition, install a single-control faucet that will take up less space than the two-handled models.
If possible, replacing a standard hinged door with a sliding door will give you more room. If this is not possible, consider turning the door around so that it opens to the outside, rather than the inside of the bathroom.
Light is important in a small room. Make use of as much natural light as you can. A skylight is the perfect way to add light. One skylight will add five times more light than a window the same way and is a great way to save on electricity bills.
Get rid of any dark corners that close in the space by illuminating them. A good way to do this is to install shelves on the walls near the ceiling and fitting lights underneath them. This not only gives you more light, it also gives you more storage space. Paint the ceiling in a light, high-gloss paint. The high-gloss surface will reflect and amplify the room's available light and make it seem larger. Perfection is critical with a high-gloss finish, as every flaw in the surface, no matter how small, is magnified.
Placing light fixtures near mirrors is another good way to add light to the room because the light will be reflected. The more reflective surfaces you can add to the bathroom, the more spacious it will seem.
Mirrors can also add depth to the room. Pace a mirror across from a window because it will create the illusion of an additional "window" in the bathroom. If this is not possible, consider installing mirrors across from each other. This is an old trick that works really well when combined with lots of light. You could also mount a wall sconce onto, or right next to, a mirror. This will make it seem like there is a sconce and space on the other side of the mirror.
Using a monochromatic color scheme for the walls, floors, and fixtures will also help make the room seem larger. It does not have to be white: any light, cool color will work. Simple is essential to decorating a small room. Stay away from busy wallpaper patterns, because they will make the bathroom seem small and cluttered. Stick with a small, subtle pattern. You want to stay away from contrasts that will break up the space.
Drawing the eye upwards is also important because it will make the room seem taller. Vertical patterns are the best way to do this. This can be done with the right wallpaper or by painting stripes in the bathroom. You could also extend wall tile up to the ceiling or add a patterned tile around the top of the walls. Any type of border along the top of the walls will help bring the eye upward. Consider adding crown moldings to both the tops of the walls and the edges of the ceiling. This fools the eye into seeing more height in the space.
Another trick that will make a rectangular room seem larger is to paint the shorter end walls a shade slightly lighter than the longer walls. Simply add one cup of white paint per gallon of color to get the right hue. Add a little more white paint and you have the perfect color for the ceiling. You could also paint clouds on the ceiling, which will give the illusion of wide-open spaces.
Larger tiles in lighter colors will also help create a sense of space. Lay the tiles diagonally because it will lead the eye away and makes the space appear larger. You should also use rectified porcelain tile. Rectified tile is more consistent in size because it was cut after it was baked. Other tile is cut before it is baked, which causes the tile to have a greater size variance. This variance is sometimes as large as one-sixteenth of an inch. Because of their consistent size, rectified porcelain tile can be placed closer together, which will minimize any visual pattern that could make the room look smaller.
If possible, consider skipping bathmats. If you feel they are necessary, choose ones that are lightly colored--preferably in a color that closely match your floor covering. Contrasting colors will break up the space and make it seem smaller. The trick is to make everything blend together.
Finally, when decorating it is important that you try to find a way to eliminate as much clutter as possible. Clutter will only make a small room seem smaller. Recessed or floating cabinets are a good option because they leave visible floor space while hiding clutter.
While it is not always possible to add more space to a cramped bathroom, you can always add the illusion of more space. This can be as expensive as you want it to be--the choice is up to you.