All straight-edge knives should be sharpened regularly to get the best results when slicing and dicing. Sharp knives make food preparation not only faster and easier but also safer: You need to apply less pressure, which means there’s less chance of the knife slipping.
In an ideal world, household knives should be sharpened on a device called a steel at least once a week.
Make sure your knife is clean and dry. Hold the steel vertically, tip down on a chopping board. Then stroke the knife’s blade downward, at an angle of approximately 20 degrees, an equal amount of times on each side (between 6 and 10 should do the trick).
Go slowly for safety’s sake: Accuracy of angle is more important than speed as you don’t want to damage the sides of your knife (or your hand!). If you don’t feel confident, it’s best to send your knives off to be professionally sharpened.
When honing your knife on a steel no longer gives you the sharp edge desired, it’s time to move onto a whetstone. Buy a high quality stone from a reliable company that can offer you advice on how to use it. A good stone will last a lot longer than a cheap one and will be a lot less frustrating to use.
NOTE: Always chop on a wooden or plastic surface; glass and ceramic surfaces are too hard on the blade. Never put your good knives in the dishwasher.