Place the material to be cut on a stable, strong surface, such as a workbench or cutting board, and mark the cutting line. Hold the knife firmly and place the point or edge along the marked line, then cut with slow, regular movements, without pressing too hard, keeping the blade at a constant angle. For clean cuts, make several lighter passes. Always keep your free hand away from the path of the blade and never cut towards your body. Do not use on materials that are too hard, such as metals, and do not lever with the blade, which could chip. After use, clean the blade with a dry cloth, dry it well and store it with a guard in a safe, dry place, out of the reach of children. To maintain the edge, sharpen it with a stone or a suitable sharpener when the cut is no longer clean.