Preheat your oven to 400F/200C. Peel and thinly slice the garlic cloves. Cut the sausage links into two strings of four sausages each.
Allow each string to unravel, so there is no division between the sausages, and massage them with your hands to even out the distribution of the meat.
Roll each string into a spiral shape onto a baking sheet with raised edges, inserting garlic slices and sage leaves at intervals inside the Catherine wheels. Insert a skewer through each Catherine wheel to hold the shape when cooking.
Cook on a middle rack for 20 min or until crispy on top. With 5-10 min remaining remove from the oven and sprinkle with olive oil and any remaining sage leaves, then put back in the oven for additional 5 minutes.