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Hand washing your clothes is a great way to save money, water and time during your next vacation.  Here's the steps to washing your clothes in the sink:

1. Check the labels on your clothes for the right water temperature - Some clothes are supposed to be washed in cold water to prevent fading and shrinking, others can be washed in warm water; so make sure you don't damage your clothes from the wrong temperature.
2. Add 1/4 cup of detergent - If you add too much than you'll be swimming in bubbles.
3. Plug the sink and add water - Again, make sure the temperature is appropriate.  Try not to add too much water; you only want to soak your clothing, not yourself.
4. Let your clothes soak in the soapy water - Depending on how dirty, smelly, and stained your clothing is, you may want to leave them soaking for longer.
5. Work the clothing between your hands - Knead the soapy and wet clothing until you feel they're washed through.
6. Unplug the sink and let it drain - Let the soapy water go.
7. Rinse your clothes - Turn on the faucet and let the water run through your soapy clothes until there's no more soap going down the drain.  You don't want your clothes to dry with soap still in them.
8. Dry 'em - If you're able to use a drier then I would recommend throwing them in to save some time, otherwise hang up your clothes to dry.

Here's a quick video about hand washing clothes: