 Sheridan had her early vocal training while at school at the Dominican Convent in Eccles Street, Dublin, with additional lessons from Vincent O'Brien.In 1908, she won a gold medal at the Feis Ceoil.From 1909 to 1911 she studied at the Royal Academy of Music in London, during which time she was introduced to the Italian inventor Guglielmo Marconi, who was instrumental in arranging further studies for her in opera in Rome.