Sandford was the eldest son of Albert Edmondson, 1st Baron Sandford, and his wife Edith Elizabeth (née Freeman, and sister to Ralph, Arnold and Peter). He was educated at St Cyprian's School, Eton, and the Royal Naval College, Dartmouth and later trained for Holy Orders at Westcott House, Cambridge. He served in the Royal Navy in the Second World War, notably at the landings in North Africa, Sicily and Normandy, where he was wounded. For his actions at Normandy he was awarded the Distinguished Service Cross. After the war he was wounded on in the Corfu Channel Incident in 1946. He was on the staff of the Royal Naval College in Dartmouth from 1947 to 1949, served on in 1950 and on HMS "Cleopatra" from 1951 to 1952, was on the staff of the Commander-in-Chief in the Far East from 1953 to 1955, and was commander of the Home Fleet Flagship HMS "Tyne" in 1956. The latter year Sandford retired from the Royal Navy with the rank of Commander. In 1958 he was ordained in the Church of England and served as Curate of the Parish of St Nicholas in Harpenden from 1958 to 1963 and as Executive Chaplain to the Bishop of St Albans from 1965 to 1968.