 She received a missionary education, including being a boarder at Mambere Girls School, a secondary school with the highest level of education then available for African girls.In 1952, when at secondary school, Wambui swore an oath of allegiance to Mau Mau and in 1954 she left home to join the Mau Mau insurgency in Nairobi after the brief detention of her father.Wambui spied on the British and mobilised women and domestic staff to obtain arms.