Turn on your washing machine. Set the water temperature to warm.
Allow the basin of the washing machine to fill. Add 1 cup of salt to the warm water while it is still filling.
Turn your denim jeans inside out and submerge them in the warm, salt water. Allow them to soak for a least 30 minutes before adding an appropriate amount of laundry detergent. Begin washing in a normal cycle.
Stop the washing machine when it hits the rinse cycle. Add 1 cup of distilled white vinegar.
Restart the washing machine and allow it to run through until the end of the cycle. Remove the jeans from the washer and tumble them dry on low heat.