The Edwardian and Victorian styles of the time are still a popular choice today. They look exquisite in a villa or cottage bathroom, and never loose their appeal in terms of design.
A very functional design can be incorporated for bathrooms as small as 5' X 8' in dimension. Sacrificing a large closet or partitioning off a small area of a larger room will provide the area needed. The first tip should be taking into account the location of electrical outlets and water sources. If these vital utilities do not already exist, the key components of the room, which are the toilet, sink and tub or shower, should be roughly sketched into the floor plan, to allow proper placement of these utilities. The second factor will be the entrance door placement, as this will determine the layout of the bathroom. If the door is located in the center of the room, the toilet and sink will usually be placed on one side of the room, with the tub or shower on the other side.
The ultimate luxury in a fantasy bathroom would have to be a waterproof TV. You could even think of doubling the bathroom up as gym, complete with exercise bike and rowing machine. Ornaments should be unobtrusive, so choose things like small piles of pebbles and modern wall prints over candles and nick-nacks.