How to sew a large puppy bed from an old duvet cover

When we were getting ready to adopt our two ex-racing greyhounds, I bought a flannel duvet cover at a charity shop, studied a couple of pillowcase patterns, and made these giant pillows. This is my step-by-step tutorial for making a large puppy bed in a pillow shape, out of an old duvet cover and duvet. Only beginner sewing skills and supplies are required!