Haha..I thought the thread title said Man U duvet cover at first...thought you were flogging one!
You need to put the corners of the duvet into the corners of the duvet cover and hold on tight to them...then you can just shake it down.
Long arms would be useful. I'm no gorilla but this is how I manage it.
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Old aunts used to come up to me at weddings, poking me in the ribs, cackling and telling me
'You'll be next.' They stopped when I started doing the same to them at funerals.
