An 'emergency kit' of club soda, vinegar, ammonia and some needed application tools is a good idea. Everyone sometimes runs out of commercial carpet cleaners just at the wrong moment. Using sponges and rags soaked in those can help remove tomato juice, and lessen the impact of dog urine or other common carpet stains.

For example, just apply club soda to a rag and soak up as much of a tomato stain as possible right away. Just as with clothes, the longer they sit, the deeper and more lasting they become. Cold water is, paradoxically, usually better than warm. Warm water is good for dirt, which it helps dissolve. Cold water slows the spilled chemical from reacting more quickly with the carpet fibers.

Once most of the spill is soaked up, a good brushing with white vinegar and a bit of laundry detergent will get most of the rest. Scrub the remaining stain, then place a dry towel over damp carpet and press it in with your feet. Carpets that stay wet too long get mildewed.

Small burns are another common problem. Even the most heat or fire resistant carpet material can be burned from a dropped cigarette or an ember from a wood stove or fireplace. In rare instances, clipping a fiber or two from a pile rug can completely eliminate the problem. In most cases, the damage is a larger spot. More extensive repairs are needed.

Whenever installing new carpet, be sure to save any extra for just such repairs. Take it out of the closet or storage shed and lay it on top of the regular carpet from time to time. Otherwise, it will be a completely different shade when used as repair material.

If you don't have any spare, it will be necessary to sacrifice a small section in an unseen area, such as the back corner of a closet or from under a piece of furniture that is never moved.

Cut out the burned area with a utility knife or Xacto blade. You'll need to remove a little of the good carpet around the burned area to ensure that it doesn't unravel. Insert the blade well into the backing between the fibers and make your cuts as straight as possible.

Using that piece as a guide, prepare a piece of replacement carpet. Err on the side of making the replacement a hair larger than the section removed. Excess can be trimmed away. A piece that's too small will be useless.

Now you have two options: whether to glue the replacement piece to the sides of the existing carpet or to the sub-floor. The latter will give you a stronger repair, one less likely to shift or come up later. But anything glued to the sub-floor will mean a more difficult job when it comes to replacing the entire carpet. Also, there is a possibility that the plywood sub-floor can be damaged when yanking up the old carpet piece.

Which technique to use depends on the location of the burn and how likely you are to have to replace the carpet in the future.