Using the Han Chan Blueberry Beauty Facial Mask is easy. First, clean your face thoroughly to remove dirt and oil. Then, unfold the mask and place it gently on your face, adjusting it to fit your facial contours. Leave the mask on for about 15 - 20 minutes. After that, take off the mask and gently pat the remaining essence into your skin. You don't need to rinse it off. As for the notes, keep the mask out of reach of children. If you have sensitive skin, it's advisable to do a patch - test on a small area of your skin first. To maintain the quality of the mask, store it in a cool and dry place, away from direct sunlight.