In geomantic omen, mirrors can ward off evil spirits. When people sleep, the energy field of the body becomes smaller. At this time, the body's resistance is weakest. Mirrors will reflect evil spirits to people, which is harmful to human health and makes people unlucky. In feng shui, this situation is called: "looking at the bed in the mirror will make people suffer from yin."
Your previous method was quite good, but it was too much trouble to draw the curtains before going to bed every day! So the most fundamental way is to take off the mirror ... just fix it with screws, but it's not impossible to disassemble it ~ ~ ~