The worst part of having a dark blue or black denim clothing is the fact that when the item is washed the dye from your dark denim piece of clothing can end up ruining other clothing items. Taking certain steps will ensure that your dark denim won't bleed all over your other garments and cost you money to replace the ruined items. Setting the dye in your dark jeans is the key to making sure the dye doesn't bleed onto other fabrics.
Set the dye in your dark jeans. Fill a plastic bucket halfway full with water, and fill it the rest of the way with white vinegar. Leave enough room in the bucket so that the dark denim item will fit once immersed in the solution.
Soak the dark jeans in the vinegar and water mixture for 15 minutes.
Wash the jeans. First, turn them inside out. Use cold water, and only launder your dark jeans with similarly colored garments made of similar fabrics. Use a gentle, mild detergent.
Dry the jeans as you normally would any other denim item.