Garau was born in Santa Giusta, a town in the Mediterranean island of Sardinia, Italy. He studied at the Accademia di Belle Arti di Firenze. He graduated from then 1974. In 1977 he became the drummer in the progressive rock group Stormy Six. After Stormy Six disbanded, he became a visual artist. He had his first solo show in 1984. He participated in the 50th Biennale di Venezia in 2003 and showed work at the European Parliament in Strasbourg in the same year.