Read the care label for the jeans before washing them.
People hand wash clothes for a variety of reasons. In some cases, the garment is too delicate for the washing machine. This is not the case with blue jeans, which are made of a sturdy fabric. However, if the jeans have a particularly nasty stain that could transfer to other clothes, washing them separately is a good idea. Another reason for washing jeans by hand is when they are new and you don't want them to bleed over your other clothes, or you recently acid-washed them or bleached them. The best way to get out all the dye and clean them is to wash the jeans in the sink by hand.
Fill a sink with cold water. Add a small amount of laundry detergent.
Swish the water with your hands to make soapy water.
Submerge the jeans in the water. Agitate them with your hand and let soak for 20 to 30 minutes.
Drain out the sink water. Refill the sink with cold water.
Let the jeans soak for 10 minutes. This helps to get out the detergent.
Drain the sink again and refill with cold water. Do this until the water in the sink is clear. This means the jeans have stopped fading.
Wring out the jeans as best you can. Hang to dry or throw them into the dryer.