1. If you wash it for the first time, you need to pour some white vinegar in the water, and at the same time turn the pants over and soak them for about half an hour to lock the color. Because dark trousers are bound to fade a little, and white vinegar can keep the azure blue as original as possible. 2. Turn the jeans over and wash them by hand in water to avoid unnecessary washing and fading; 3. Please do not soak the pants in hot water, it will shrink to a large extent, and the water temperature should be kept below 30 ℃. 4. Use mild detergent, do not use bleach or any product containing bleach or fluorescent agent; 5. If the jeans are not oily or otherwise dirty, reduce the amount of washing powder as much as possible, or even wash with water; 6. When drying the jeans, be sure to hang them flat from the waist (fix them with clips, do not pull them tight) and turn them over to dry them. Dry them in a dry and ventilated place to avoid sun exposure, which can easily cause serious oxidative fading or hardening.