It occurred to me while changing my bedsheets yesterday that perhaps not everyone does it the same way, but it also occurred to me that i've only ever done it one way and i couldn't even begin to think about how it could be done another. So here i am, asking all the mundane questions nobody else can be bothered to think about. This is how i do it (for reference, on a double duvet): 1. Lay the cover on the bed (or similar flat surface) open-end facing you, and hold each corner of one side of the duvet, with the rest of it falling to the floor between you and the cover. 2. Push each corner into the cover and lift the cover whilst doing so, to more easily reach right into the corners. 3. Once the corners are in place, carefully swap positions so you're holding the outside of the corners rather than the inside (i tend to hold the middle with my chin here to stop the corners moving out of position); whilst holding the outside corners lift the duvet high and give the whole thing a good shake to move the cover down the duvet as much as possible. 4. Place it back on the bed and push the corners of the open end into place and button that side up. 5. Give the whole thing a good shake from multiple angles to get rid of any lumps and when satisfied place on bed.