From the World Health Organization:

How to put on, use, take off and dispose of a mask

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  • Before putting on a mask, clean hands with alcohol-based hand rub or soap and water.

  • Cover mouth and nose with mask and make sure there are no gaps between your face and the mask.

  • Avoid touching the mask while using it; if you do, clean your hands with alcohol-based hand rub or soap and water.

  • Replace the mask with a new one as soon as it is damp and do not re-use single-use masks.

  • To remove the mask: remove it from behind (do not touch the front of the mask); discard immediately in a closed bin; clean hands with alcohol-based hand rub or soap and water.

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