To test if a fabric is colorfast, look for a small hidden area of the item to be washed such as the underside of a clothing hem or a hidden corner spot of a carpet. Wet the area and apply a drop of the cleaning agent (detergent, carpet cleaner, etc). With the use of a white cloth or rag, dab the area and check to see if the color or fabric dye comes off. If it bleeds, wash it separately from other laundry items. After applying the cleaner, you may also want to wash the area with water and let it dry. The fabric is colorfast is if you cannot spot any fading or discoloration in the fabric.