All rugs can use a good overall cleaning occasionally. But if you have a small stain or flaw that you want to address immediately without having the entire rug cleaned, spot cleaning is an important skill to have in your arsenal. Following are spot cleaning techniques for a few different scenarios:
Get it while it's wet. Once a stain dries, it's much more difficult to remove. Get to it when it's still wet and you have a much better chance and easier time of removing it completely.
Always blot. Start at the outside of the stain and work your way inward to avoid spreading.
Start with water only. Start with the least invasive solution (water) and always test if you need to use something stronger. Water-based stains that should be able to be removed by simply blotting with water, blotting with a dry towel, and repeating (sometimes many times): alcoholic beverages, berries, soda, pet accidents, food dye, milk, dirt, washable ink, wet latex paint.
Removing sticky spots (like gum or wax) from wool rugs: Use cold to harden sticky areas by putting ice cubes in a plastic bag and holding them to the rug. Once hardened, scrape the area with a spoon. Blot with rubbing alcohol to remove any remaining residue.
Spot cleaning natural fiber rugs like sisal, coir, or jute: Using warm, soapy water, scrub the stain with a soft brush. Rinse well and blot with a towel to dry. Dry as thoroughly as possible, as water weakens these natural fibers. Cleaning can be done in place, with plastic sheeting laid under the stain to protect the flooring beneath.
In our research, we found this amazing chart for removing every imaginable stain from many common rug fibers. Check out the matrix at Oriental Rug Cleaning.