Water, though used for many cleaning projects, can leave behind some unpleasant stains of its own. For example, if you spill water on your carpet and fail to clean it up immediately, you may find yourself with brown staining, a result of the moisture absorbing dirt from within the carpet and bringing it to the surface. If you notice these types of stains on your carpet, you will need to attack them with a powerful cleaning solution.
Pour one cup of water into a clean, empty spray bottle, and add 1/4 teaspoon of any mild dish detergent. Allow the detergent to absorb into the water. This simple mixture provides one of the most powerful solutions for most stubborn carpet stains, including those relating to dirt and moisture, according to Good Housekeeping.
Spray the liquid solution onto a dry, soft (nonabrasive) cloth. Hold the bottle several inches above the cloth, and allow the liquid to mist softly over the fibres. You do not want to clean your carpet with an overly saturated cloth, as this can exacerbate your problem.
Dab your brown carpet stain gently but rapidly with the cloth until the stain absorbs the liquid and begins to break up. As the stain loosens, begin dabbing with a dry section of the cloth. Do not at any time rub the stain, as this can spread it. Continue dabbing until the stain vanishes.
Dampen a second soft cloth with clean water, and dab your carpet again to remove the detergent left behind. For best results, use your spray bottle (or a second spray bottle) to mist clean water onto your second cloth, and then begin dabbing the carpet, once again cleaning the fibres without soaking them.
Dry your carpet. To ensure total moisture elimination, place a stack of absorbent paper towels on top of the damp spot, and place a heavy object (such as a vacuum cleaner or small piece of furniture) over the paper towels to weigh them down into the carpet. Leave the objects overnight.
Sprinkle baking soda over the stain. This will absorb any lingering moisture that can resurface, and restore a pleasant aroma to your carpet. Wait approximately two to three hours, and vacuum the area.