As a teenager Colvig ran away to join the circus. He eventually performed as a circus clown. In 1946 he was hired by Capitol Records to work on the world's first read-along book “Bozo at the Circus.” The book and record were a tremendous success and there were demands by children to see Bozo. Drawing on his circus background, Colvig created a clown character to match the books and records. Station KTTV in Los Angeles created a television series for Bozo the clown starring Pinto Colvig. After Bozo, Colvig returned to doing voice work.