How can I get my duvet cover to stay on my duvet properly?
I have a queen size duvet and bought a duvet cover last week. I toss and turn a lot at night, and the duvet gets sorta folded up inside the duvet cover, like the corners don’t match up, etc. and its a pain to fix! anyone know how I can stop this from happening? (besides tossing & turning)

You could sew some velcro tape on the inside of the duvet cover and match it up with the other side of the velcro sewn onto the duvet. I would concentrate on doing this near the edges but if you still find it separating then do it toward the middle too.