First, some recommendations
First of all, no need to rush to put your jeans in the washing machine after each wear, they don't need it. Wash it only a few times per season to protect the canvas fibers, especially if you machine wash it. Even if you decide to wash it by hand, you can completely let several weeks, or even several months, pass depending on how often you wear it, between each wash as long as you air it regularly. It is advisable to wait until you have worn them several times (not necessarily consecutively) before washing jeans.
It's cowboy spirit, and it's also synonymous with saving energy and water #bravovous
Always wash your jeans inside out and with other clothes to make their color last. We love the natural faded marks on the buttocks from sitting or bending knees...but we avoid the weird marks left by the drum of the machine. Inside out and cushioned by other clothes, you'll be fine! Do not use artificial softeners or bleaches - and therefore avoid washing powders which contain them and which may affect the color of the fabric. The ideal way to keep your Donna black is a detergent for dark textiles. For your laundry, choose an Ecocert and/or Ecolabel certified product. Remember to checkthe hardness of the water in your municipality(its concentration of calcium and magnesium) to properly dose your maintenance products and take care of your machine. In fact, the harder the water, the more it scales the machines, which reduces their efficiency.
Avoid the dryer which breaks the fiber of clothes and which consumes a lot of energy. Prefer drying in the open air, flat, always upside down.