Even though you've probably been washing your hands for years, there are quite a few steps that most people either don't know or don't practice. For example, placing your hands under the water before adding soap can help you build up a lather for a better cleansing. Once your hands are lathered up, you should always wash them for at least 20 seconds, or the amount of time it takes you to sing "Happy Birthday" to yourself twice at a regular speed. You should rub your hands together vigorously, though you should be sure to spend some time cleaning your wrists, the backs of your hands, between your fingers and underneath your fingernails. Also, make sure to rinse your hands completely when you're done so that you don't leave a residue.
Once you're finished, it's important to make sure you avoid recontamination before leaving the sink. For example, if possible, use a towel or tissue to turn off the faucet and open the door so you avoid touching areas that typically hold a lot of germs, particularly in public restrooms [source: Centers for Disease Control and Prevention].
Now that your hands are nice and clean, there's still the problem of drying them off. On the next page, read about different ways to safely dry your hands.