Baynes was born in Boscombe Hospital, Bournemouth. Her mother was Margot Findlay and her father was Leslie Baynes, an English aeronautical Engineer, who designed what is believed to be the oldest flying glider in the United Kingdom. As a girl in the 1970s Baynes attended the Elmhurst Ballet School in Camberley in Surrey, where a contemporary was the Actress Laura Hartong.