What to do about this pain in my foot?

Rest, ice, elevate: Well, the first step would be correcting the cause. Was there trauma/injury or anything that needs acute treatment? Is it red or swollen? Arthritis or gout may be cause and can be treated with anti-inflammatories such as naproxen. If it looks normal, but just hurts, then rest it, avoid aggravating activities, elevate it, ice it and maybe naproxen/ibuprofen. Persists more than a few days? See doc.