You need a hand file, work gloves, and a well-lit workplace are some essentials to consider. To approach, you need to clean the crampons first, rinse them with water, and let them dry. The next step is filing the edges, which needs you to be fully concentrated. After filing, you can test the sharpness and clean them with wipes. This is real professional work. And if you are not skilled, we recommend taking your crampons to some professional.