Wash properly and you can extend the life of your garments.
1. Wash moderatly - From an environmental perspective the best thing would be not washing at all. But most garments need to be washed every once in a while. If a garment is not visibly dirty it is sometimes enough to air it. This is especially true of wool that have the ability to clean itself.
2. Fill up the machine - Many modern washing machines weigh the laundry to use the right amount of water. In older machines this faunction is rare and it is therefore advisable to take the habit of always filling the machine.
3. Prewash is rarely needed - A prewash is only necessary if the clothes are very dirty.
4. Avoid softeners - Softener is not nice to the environment and when washing with softener it will follow the waste water. Certain garments and textile fibers are even damaged by softeners. Function clothing loses its ability to breathe and absorb moisture and towels get poorer absorption capacity. A cheaper and more environmentally friendly alternative for softer clothes is to use a small amount of vinegar instead of softener.