There's nothing quite like sinking your toes into a soft, plush carpet. Today, wall-to-wall carpeting is easy to find in textures, colors and pattern to complement or contrast with every of decor and lifestyle. There are several key factors that you need to consider in addition to your budget, the warranty period, and whether carpet is actually the right flooring choice.
1. Padding Just as a building needs a solid foundation, carpeting relies on a layer of padding for support, strength and a bit of extra cushioning. You can't see the padding, but you'll definitely spot the extra wear and tear on your new carpet if you pick an inadequate padding material. Often made from rubber or foam materials, carpet padding conceals subfloor imperfections to improve the appearance of the finished floor. It acts as insulation to help control the temperature of your home, and absorbs sound to protect your privacy and eliminate neighbor noise. The right padding supports your carpet through years of use, since it prevents carpet backing and fibers from coming apart over time. I like to use firm, dense padding in high traffic areas like hallways and family rooms while guest bedrooms and other light-traffic rooms need less protection. The Carpet and Rug Institute recommends a 7/16-inch (11-millimeter) padding with 6 pounds (2.7 kilograms) of density per cubic feet to support cut pile or cut loop carpeting. For Berber or thin loop rugs, look for a 3/8-inch (9.5-millimeter) pad or thinner, with 8 pounds (3.6 kilograms) of density per cubic foot.
2. Style: Some typical styles include plush, Saxony, Berber, textured and frieze. These terms apply to its pile, which is the surface you see, created from yarn tufts that are either folded over into loops, cut straight across or both. While each style has a distinctive look, that shouldn't be your main consideration. Instead, look at how well your lifestyle meshes with a particular carpet style. Plush carpeting, for example, is made from tightly twisted pile, and is thick, soft and inviting. But it also shows footprints and vacuum tracks, and can develop something called "pooling," or areas that appear shaded because the normal direction of the carpet fibers has been reversed. Saxony, the most common type of carpeting, is similar to plush.These carpet styles work best in low-traffic areas like formal living rooms and master bedrooms. Woven or loop-pile wool should be confined to dressing areas. Nylon and other synthetic carpets are a better choice for splash zones; these are washable and hold up well in moist conditions. Berber carpeting, in contrast, is crafted from continuous fiber loops and is flat and dense. It can have a level loop, cut-and-loop or multi-level loop design. All of these attributes mean Berber is extremely durable and doesn't show tracks, soil and stains -- perfect for high-traffic areas, or places frequented by kids. Friezes are a cut-pile carpet made from slightly twisted fibers. The look is less formal than plush, but fancier than many textured pieces or Berber. The carpet feels soft on your feet, yet its fuzziness hides footprints and dirt well. Textured carpeting is made from fibers cut to different heights, which causes them to reflect light. This makes it difficult to see tracks and dirt. So this type of carpeting is also great for high-traffic areas. Some Berbers are textured.
3. Maintaining your carpet: One of the best ways to ensure you'll be satisfied with your new carpet is to stick with carpeting you can maintain easily. Homeowners with children or pets should avoid hard-to-clean shag or high-end rugs. Stain-resistant carpets can eliminate the frustration associated with spills and may cut your cleaning time. Know how often you'll need to clean and what special equipment or products the manufacturer recommends. Skip carpets with extensive maintenance requirements unless you have the extra time to perform these tasks. The principal care of carpeting is regular vacuuming – easy enough. And since most carpet today is manufactured with a stain resistant treatment which doesn’t allow liquids to pass below the surface, you can sop up spills easily. But do it immediately. Stain guards are only so strong. 
4. Fiber type: Generally there are two types of fibers natural and man-made (synthetic) fibers. Wool is the luxury choice for softness, durability and even cleaning. You’re going to pay $50 to $100 for a square yard. Nylon is not as durable as wool but costs a lot less. It’s soft and good at resisting stains. You can cover your floor for about $18 to $35 a square yard. Olefin is a good choice for commercial use as well as indoor/outdoor use since it durable and water- and stain-resistant. It’s best used in low pile carpets since it’s less resilient than nylon and can mat or crush. The average cost is $9 to $16 a square yard. Polyester has a soft texture, and is known for its luxurious thick pile but low durability. Expect to pay about $11 to $19 per square yard. Acrylic feels and looks like wool but then tends to fuzz. It’s not usually used in room-sized carpets and you’ll most often come across it used in bathroom rugs since it moisture and mildew resistant. Expect to pay $10 to $15 a square yard.
5. Toxicity: Carpeting can aggravate allergy symptoms as the fibers catch and hold dust, dirt, bugs and bacteria. If you suffer from dust mite or similar allergies, or have respiratory conditions such as asthma, you should think twice about using carpet in your home. Wool is often a good choice, however. Many people are shocked to learn just how much carpet, padding and adhesives can impact air quality and health. If you've ever been around brand-new carpet or other building materials, you probably remember that distinctive "new" smell. That odor is caused by volatile organic compounds (VOCs). VOCs, such as formaldehyde, cause poor indoor air quality and can contribute to a host of health problems, including asthma and allergies Protect your family by choosing carpet made from natural products, including wool, jute and other organic materials. Also, look for organic or chemical-free dyes to keep toxic fumes out of your home.
6. Sustainability: In addition to impacting your health, your choice of carpet can also affect the environment. Reduce your impact with recycled materials, such as carpets made from recycled water bottles. Many manufacturers also use recycled carpeting to produce new rugs, so check the recycled-content percentage before you buy. Keep in mind that nylon and other synthetics are made primarily from fossil fuel byproducts, so choose renewable or recycled products for maximum sustainability.