Snipers are taught to camouflage themselves in an environment. They have certain equipment that can help them. A sniper can also be given a ghillie suit depending on the environment he will be deployed to. Snipers also tend to cover themselves in foliage, hide in thick trees and bury themselves in the dirt.
Snipers are also trained not to be afraid of the fauna in the areas they are deployed to. They are literally raught to be calm when a snake creeps up near their face. This requires nerves of steel. Sniping is an artform not suited to every soldier.