Cois was born in Fossano. He played for several clubs throughout his career, including Torino (1988–1994), Sampdoria (2002–03) and Piacenza (2003). He achieved notable success with Torino early in his career, after achieving Serie A promotion by winning the 1989–90 Serie B title with the club. He later won the Mitropa Cup in 1991, the Coppa Italia in 1993, and he helped his team to the 1991–92 UEFA Cup final, after helping his team to qualify for the tournament by leading them to a third place in Serie A in 1991. In the 1992 UEFA Cup Final, they were defeated by Ajax on aggregate.