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Dark clothing requires extra gentle washing and can also bleed onto lighter clothes if they're washed at the same time. Therefore, always separate dark and light clothing before doing laundry. Darker garments should be washed separately. The less exposure dark fabrics get to water and detergent, the better. Turning your clothing inside out before washing it minimizes contact with water and soap. For best results, look for a detergent specifically formulated to wash dark clothes. A basic detergent that's free of additives is your best option. Avoid things like "color-safe bleach," as no bleach is actually 100% color safe. While you should avoid most additives, a built-in fabric softener is a good idea, especially one specifically formulated for dark clothes. Pick the shortest cycle offered by your washer or dryer. A briefer cycle minimizes dark clothing's exposure to water and soap, reducing the amount of damage it accrues. Choose the coldest water setting possible. Cold water does not cause as much fading and bleeding in the wash. Never wash dark clothes in warm or hot water. White vinegar can help prevent the build up of residue from detergent. Detergent residue is a major culprit in dark clothing becoming faded. During the rinse cycle, open your washer and add a cup of white vinegar. The less time dark clothing spends in the dryer, the better. It's best to hang your dark clothes to dry. Do not hang your clothes in direct sunlight, however, as sun exposure can fade color.

Summary:
Separate dark and light clothing. Turn dark clothing inside out. Pick a detergent for dark clothing. Opt for a shorter cycle. Use cold water. Add a cup of vinegar during the rinse cycle. Hang dry your clothes.