Cousin made his debut when first team regular George Merchant was injured and one month later, he scored his first goal for Dundee in a 5–1 friendly victory against Manchester United, who had just become the English champions.
After establishing a first-team place, Cousin attended St. Andrews University to study Greek and Latin for an Arts Degree, whilst combining this with his early professional footballing career.
He played in attack for Dundee alongside Alan Gilzean in a team considered by Bob Crampsey to be the best produced in Scotland since the Second World War.
[7] Cousin was dubbed the 'King of the double shuffle' [8] because of his ability to repeatedly outwit opposing players, by stepping over the ball.
[9] Cousin began a teaching course in Dundee after completing his degree, before he took up the post of Classics teacher at his old school, Alloa Academy.