What can I do to remove ringworm on my leg?

Topical antifungals. Apply a topical antifungal treatment that you can buy over the counter to the involved skin several times a day for 2 to 4 weeks until 1 week after the rash has resolved. You can use the same treatments that are advertised for athlete's foot in the drug stores. They can contain terbinafine, miconazole, Clotrimazole or another azole.