During the early stages of his career, Arnold had stint with non-league Boreham Wood and spent six months with Arsenal's Under-15s.|
Four days before his 17th birthday, Arnold was taken on by Norwich City as a trainee having impressed scouts. He was named as an unused substitute for Norwich's second round Carling Cup clash with Rotherham United on 19th September 2006.
Arnold signed a professional contract with the Canaries on 11th May 2007, and appeared on the bench 11 times throughout the 2007/08 season. He made a number of reserve team appearances, including the two fixtures against Grays. However, he failed to make a first team appearance.
The young goalkeeper signed a one-year deal with Grays Ath on 12th June 2008, having been released in May by Norwich City, alongside eight other players.
Details corrected as of 12th June 2008