Preheat your oven to 200 °C.
Your pork skin needs to be dry. You can pat this over with kitchen towel, then, with a sharp knife score the skin down to the fat (but not too deep). Rub the olive oil and salt into the skin, use a baking tray with a rack in it so that the fat drips away and place in the oven for 50-60 minutes. You can check your crackling is ready by tapping with a knife, if any of the skin is not crispy pop back in the oven. Pork crackling tastes great with a salad, a beer or just in a bowl.