Remove solid stains from the carpet. Blot up liquid stains from the front side of your carpet, using paper towels or white rags. Turn the rug over and blot up as much liquid from the back as you can.
Fill a bowl with 2 cups of warm water. Add 2 tsp. of natural or gentle fabric detergent to the water and mix it with a spoon until the mixture becomes sudsy. This is your detergent solution.
Add 2 cups of warm water to a second bowl, then add 2 tsp. of white vinegar, which will neutralize the stain. This is your vinegar solution.
Blot the affected area with your detergent solution, applying the solution with a clean rag. Press the rag to the rug, then lift and press the rag again in another spot. Don't scrub the cleaning agent into the rug, since this just works the stain into the rug fibers. Stop once you've coated the area with the detergent solution.
Press a clean rag into the detergent solution to draw out the soap and the spill. Continue to press to remove the moisture. Once you've drawn out as much as you can, stop.
Dip a rag into the vinegar solution. Blot the affected area with vinegar, working in the same manner as you did for the detergent.
Blot out the vinegar using a clean towel.
Blot the stain with the detergent solution one more time, then blot out the detergent.
Rinse the stain with a rag soaked in cool water. Blot out the water with a clean rag.
Let the Persian rug dry naturally. Your should not see -- or smell -- the stain when the rug dries.