Correct the unwanted behaviour only if you catch the dog in the moment, e.g. tearing up a blanket, chewing on your shoe. If you shout “BAD DOG!” when the dog is already done with the destruction and is relaxing on their bed, the dog will just think you are crazy and unhappy that they are sleeping on their bed, which was fine before… Is correcting behavior allowed in positive training?
Chasing your dog in order to get the shoe back or pulling on a blanket will make it only more amusing to your friend and encourage the behaviour.
In the situation, think of “What you want your dog to do instead”. For example, offer a chew toy instead, ask for a few obedience tricks and start engaging with your dog. It is your responsibility to schedule regular play sessions and interactions with your dog so they don’t seek your attention with this negative behaviour, which will definitely catch your attention.