How do I have to fold a emergency slide so it can be reused?
WARNING

These slides may contain explosive squibs and/or chemicals not safe for ingestion and it is NOT SAFE to mess with them if you do not know what you are doing! If an airbag in a car can kill or cause injury, imagine an enormous version of that. If one became available for sale, I would be very cautious as to whether it had been made safe/inert. Tread carefully.

Only authorised life support fitter type maintainers at the factory or the approved delegated authority will be able to fold slides up again to the correct standard. It is a specialist type job and a jigsaw puzzle. It is similar to trying to get a tent back in it's bag if you don't use the correct technique.

As with all aircraft maintenance tasks, it may sound like a cop out, but the answer to any how do you do that question is "in accordance with the approved procedure". Find the approved procedure and you will know. It will be in the airbus manual or from the manufacturer of the slide.