how to describe the steps of washing hands.

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I agree with Nixxtixx. Here are some other ways to say it:

Simple:
1. Turn on the water.
2. Wet your hands.
3. Apply soap.
4. Rub your hands together.
5. Rinse off the soap.
6. Turn off the water.
7. Dry your hands.

Complex:
First, turn on the water faucet. Place your hands under the water to wet them. Then, put some soap on your hands and scrub your hands until it (the soap) lathers. Be sure to get the fronts and backs of your hands, and to also clean under your fingernails. Rinse your hands under the water until the soap has been washed away. Finally, turn off the faucet and dry your hands.