When some people think about decorating, they imagine hordes of furniture, gallons of paint, and an endless array of curtain swatches and wallpaper samples. Furniture and color schemes certainly play an important role in creating a total look, but they're not the only element of interior design.
Using rugs as part of a theme is one of the most satisfying (and easiest!) ways to spruce up a room. If your living room has Southwestern furniture and/or art, then a complementary Navajo or Southwestern style rug helps to carry the design elements throughout the entire room. If a child's room has carnival colors, a modern polka dot rug adds to the overall look and feel. It's easy to find rugs for almost any theme and these rugs offer more than just color and shape.
If you're thinking about a rug to enhance a certain theme, the first step is to decide what your "official" theme is. That might sound silly, but with some decorating styles, a theme could be hard to pinpoint. If the room has an obvious theme, narrowing down the rug choices becomes far easier.
If a room's theme isn't well defined, you can pin it down by looking at the elements (furniture, art, etc.) of the room and finding common aspects. Ask yourself a few questions: Which colors are most noticeable? What patterns or designs stand out? Does the room have a classical feel or more of a contemporary feel? Are there antiques and/or curios in view? Does the room remind you of a serene country setting or more of an urban locale? Hey, maybe it's not so hard after all!
Even if you're not able to clearly identify a theme, you'll still be able to select the right rug(s). Think about your responses to the questions above and pick a rug that matches or complements the more noticeable elements of the room.