Before touching a clean medical mask, wash your hands thoroughly with both soap and water.  Once you’ve applied soap to your wet hands, you should rub your hands together to wash them for at least 20 seconds before rinsing them off.  Always use a clean paper towel to dry your hands, and then place that paper towel into a trash bin. Once you’ve taken a new (unused) medical mask from the box, check it to ensure it doesn’t contain any defects, holes or tears in the material.  If the mask has defects, holes or tears, throw it away and select another new (unused) mask from the box. In order for the mask to fit as close to your skin as possible, the top portion of the mask will have a bendable, but stiff, edge that can be moulded around your nose.  Ensure this bendable side is facing upwards before applying the mask to your face. The inside of most medical masks are white in colour, while the outside has a colour of some sort.  Before applying the mask to your face, make sure the white side of the mask is facing towards your face. There are many types of medical masks available, each with different methods of attaching the mask to your head.   Ear Loops — Some masks have 2 ear loops on either side of the mask.  These loops are normally made of an elastic material so they can be stretched.  Pick up this type of mask by the loops, put 1 loop around one ear and then put the other loop around your other ear.  Ties or Straps — Some masks comes with pieces of fabric that are tied around the back of your head.  Most masks with ties come with upper and lower ties or straps.  Pick up the mask by the upper ties, place the ties around the back of your head and attach them together with a bow.  Bands — Some masks come with 2 elastic bands that are placed over and around the back of your head (as opposed to around your ears).  Hold the mask in front of your face, pull the top band over the top of your head and place it around the crown of your head.  Then pull the bottom band over the top of your head and place it at the base...

TL;DR in Chinese:
清洁双手。 检查医用口罩是否有瑕疵。 正确辨别口罩的上方。 确保正确的一面朝外。 戴上口罩。 调整鼻夹。 如有必要，系上口罩的下缘带子。 将口罩贴合脸部和下巴底下。