Caring for a cast iron mold is very simple. Here are the most important tips:
Cleaning: After use, clean the mold with hot water and a brush. You should avoid using washing-up liquid as it can damage the natural patina.
Drying: Dry the mold thoroughly, preferably on the stove at low heat.
Oiling: As soon as the mold has cooled down, rub it with a thin film of oil (e.g. cooking oil). This protects against rust and preserves the patina.