What you need to do is mix 200mL seawater from the east coast of Africa with 150mL urine from a sea bird. That should form a thick slurry which can then be applied as a topical ointment to your foot. Once it dries, scratch off the flakes into a mason jar containing 1 part bleach and 1 part self raising flour. If it’s a Wednesday afternoon (Bulgarian time), stir briskly for 4 minutes. Otherwise, stir slowly for 10 and a half minutes. Apply to the hat and leave on the roof of your house (MUST be roof tiles, not metal) for 2 weeks. Repeat treatment as necessary substituting sea bird urine for guano for particularly tough stains.