What is the best way to sharpen a knife without sharpener?

1. Use a whetstone. A whetstone is a rectangular or round stone made from a hard abrasive material, such as silicon carbide or aluminum oxide. To use a whetstone, first soak it in water for a few minutes to soften it. Then, hold the knife at a 15-20 degree angle to the stone and move it back and forth, applying light pressure. Continue sharpening the knife until you feel a burr (a small ridge of metal) on the opposite side of the blade. Once you feel the burr, flip the knife over and sharpen the other side of the blade. Repeat this process until the burr is removed from both sides of the blade and the knife is sharp.

2. Use a ceramic mug. If you don't have a whetstone, you can also use a ceramic mug to sharpen your knife. To use a ceramic mug, first turn it upside down so that the bottom is facing up. Then, hold the knife at a 15-20 degree angle to the bottom of the mug and move it back and forth, applying light pressure. Continue sharpening the knife until you feel a burr on the opposite side of the blade. Once you feel the burr, flip the knife over and sharpen the other side of the blade. Repeat this process until the burr is removed from both sides of the blade and the knife is sharp.

3. Use a piece of sandpaper. If you don't have a whetstone or a ceramic mug, you can also use a piece of sandpaper to sharpen your knife. To use sandpaper, first cut a piece of sandpaper that is about 6 inches long and 4 inches wide. Then, place the sandpaper on a flat surface, such as a table or a countertop. Hold the knife at a 15-20 degree angle to the sandpaper and move it back and forth, applying light pressure. Continue sharpening the knife until you feel a burr on the opposite side of the blade. Once you feel the burr, flip the knife over and sharpen the other side of the blade. Repeat this process until the burr is removed from both sides of the blade and the knife is sharp.