For ringworm you need to treatments, an internal treatment and external treatment.
An internal one would involve taking black walnut extract (kills parasites), trace minerals, vitamins, antifungals, HCL, probiotics, etc. to kill down the parasites and candida and replenish the body.
An external one would involve taking antifungal shampoos that specifically help treat ringworm. I know of two products that work very well to kill ringworm:
Everclean dandruff shampoo:
(sold elsewhere as well)
Selsun Blue dandruff shampoo medicated (contains selenium sulfide)
(all places online pretty much)
Also, taking sulphur or selenium in vitamin form specifically helps with skin conditions (and thus is why its in the shampoo).
Be sure to change your bedsheets frequently including pillow cover, and wash your clothes/hats as often as possible.