He made his debut in late 1906 at the age of 16, and by the time he was 18, he was already employed at Haydon's Road CoE School for boys.

After spearheading the attack for several seasons, the club became homeless, and Cooper-Smith was among the Dons who established Merton F.C. in 1910. In 1913, he journeyed to the Spanish Basque region with the team, facing a combined Athletic and Bilbao side two days after both teams had participated in the Copa Del Rey final. The 12-player contingent also included George Williamson, Jimmy Bouldon, W. Reeves, and Bill Davis. Following a 1-1 draw in an impromptu exhibition match against Ilford, Cooper-Smith netted the equalizer in a 1-3 loss to Athletico that was not reflective of the game's balance.
In the mid-1920s, he relocated his family to Hatfield in Hertfordshire and became a member of the Hatfield Cricket Club. There, he achieved the batting prize in 1930 and 1931 and notched up 132 runs in a single inning in 1930, setting a club record that remained unbroken until 1956, which, by coincidence, was also the year he passed away.