Wall to wall carpets are expensive. The best way to make carpet last longer is by keeping it clean. Just like sandpaper, dirt can be the abrasive that causes carpet fiber to wear.
Regular vacuuming and annual steam cleaning are the best ways to keep carpets from wearing out. Just because a carpet is labeled stain resistant, does not mean it is spill proof, so take action quickly to remove a stain before it has a chance to penetrate.
To avoid transferring color, always use a clean white cloth or white paper towels to pick up as much of the spill as possible. Blot the area, but DON'T rub or scrub since this can set the stain. For pet stains and ketchup, neutralize the area with a mixture of one tablespoon ammonia and 1/2 cup of water. For sauces or ink, apply a small amount of rubbing alcohol to a clean cloth and blot. Wine and coffee carpet stains should be treated with a mixture of 1/3 cup of white vinegar and 2/3 cup of water. A little hydrogen peroxide works well on very stubborn carpet stains.
After using the proper cleaner to remove the carpet stain, wipe the area with a mixture of 1/4 teaspoon dishwashing liquid and 1 cup of water, then rinse. It's best to remove any residual moisture from the cleaning process with paper towels. When completely dry, vacuum. Protect your investment, even if it's underfoot.