What precautions should I take when installing the toner cartridge to protect the Photosensitive Drum?

When opening the Cartridge Cover, be sure to remove the cartridge in advance to protect the Photosensitive Drum from light. Cover the Photosensitive Drum with 5 or more sheets of paper to block light, and do not place the cartridge in a location exposed to direct sunlight such as near a window. (Page 24)