Enable the stone to dry on its own. Set it inside of a dry area from dampness to stop micro organism development. Then, rub a dry pumice stone above the pilling in round motions. Do not push far too tricky given that you do not need to damage the fibers https://edenproductsltd.co.uk/2025/04/17/the-history-of-pumice-stone-from-ancient-civilisations-to-modern-day-uses/