The first aspect is color. The second is the pattern. You must consider both architecture and size. In a large room, busy patterns with tiny information can be distracting. They add depth and interest to a small intimate bedroom or bathroom, however. Large scale patterns can quickly become the focal point of a room, ideal in a large bedroom or dining area. If the design is wide enough, it may shift from wallpaper sticker printing to artwork, making an even more significant impact.   

And there's the pattern itself, of course. The pattern possibilities are virtually infinite, whether they are floral, stripes, abstract, or organic. It can, however, complement your overall design scheme, whether it's industrial, shabby chic, or a combination of conventional elements. If you want an eclectic look, choose an unusual pattern with a bright backdrop. It's easier to narrow down your options when you know the atmosphere you want to develop.  


Last but not least, there's texture. A room's depth and life are enhanced by texture. As the light reaches the wall, the surface will absorb it and cast tiny shadows or reflect it and brighten the room. A natural grittiness could be added with an organic pattern with a rugged texture, whereas a smooth toile adds elegance.   

However, it would be best if you also remembered the room's intent. If the surface is smooth, it is easier to clean a wall that could have tiny hands running through it every day. Bathrooms and kitchens are two more places where texture can obstruct maintenance. Dingy walls are one of the few things that can ruin a healthy mood.