You should not treat ringworm with vinegar because vinegar does not have antifungal properties, according to WebMD. You can use vinegar to treat other types of skin infections, like shingles.
WebMD does state that you can safely treat ringworm at home by applying an antifungal cream or gel containing miconazole or clotrimazole. Apply the cream or gel to your skin after washing and drying the infected area. The cream should be applied for about two weeks.
If the rash does not go away after treatment or spreads, you should make an appointment with your care provider. You should also call a doctor if the rash begins to look red or swollen because this could be a sign of bacterial infection.