How do you shrink a crisp packet in a oven?

To shrink a crisp packet in the oven, preheat the oven to around 200°F (93°C). Place the empty packet on a baking tray lined with parchment paper, ensuring it lays flat. Heat the packet for about 10-15 minutes, watching closely as it shrinks and curls up. Once it has reached the desired size, remove it from the oven and let it cool before handling.