A knife is a basic tool used in everyday cooking situations or by hunters and campers in the woods. A knife with a sharp edge makes cutting much easier. Through use, a knife's edge can dull over time, eventually getting too dull to be effective -- even making it dangerous to use. A knife sharpener is the best way to get a sharp edge on a knife. If a sharpener is not available, common household items, or those found in nature, can be used to restore the sharp edge of a blade.
Find two large flat rocks (river rocks work best) and grind them together to flatten their surfaces even more. Rub them together until their surfaces are as flat as possible, without any high spots.
Determine which rock has the flattest surface, then pour some water on to the surface to lubricate it.
Hold your knife at an angle between 15 and 35 degrees and swipe the blade across the surface of the rock in a slicing motion. Keep the angle consistent during the swipe. Flip the blade over and do the same on the other side of the blade until you achieve a sharp edge.
Tie a leather belt around a tree and pull the other end tight. Alternatively, you can step on one end of the belt and pull up on the other end to make it tight. Pour some water on the belt and rub some dirt into the wetted area. Rub the dirt into the belt to make a gritty paste.
Drag your knife backwards along the leather belt. The leather and dirt will polish the microscopic fine burrs on the edge of the knife. This method is called stropping.