Using these sheets is a breeze. Just put the fitted sheet on your single 40 - cm bed, making sure to align it with the tags for a perfect fit. Then add the flat sheet and pillowcases. For a more stylish look, you can tuck the edges neatly. When it comes to washing, use a gentle cycle with mild detergent in warm water. Avoid using bleach as it can damage the fabric. After washing, tumble dry on low heat. This will help maintain the softness and durability of the sheets. If you notice any stains, treat them as soon as possible before washing. With proper care, these sheets will serve you well for a long time.