Dispose of waste properly
Bring just the right amount of equipment and food (without excessive packaging), bring all the garbage home, and carefully handle anything that must be left on site. If you do need to go to the loo in the wild, dig a hole of 15-20 meters deep, away from water sources, camping sites, hiking trails, and sewage systems. Cover the hole with soil afterwards and do not leave excrements under rocks, since excrements decompose slowly and easily make water dirty. The best way is to bring excrements down the mountains.