The 22-year-old goalkeeper, who has recently penned a new contract with the club, played 13 times for the U's last year when first-choice Dean Gerken was injured, before being edged out by loanee Jimmy Walker.
Cousins now faces a straight battle with the experienced Gerken for the number one jersey and he is ready to stake his claim.
He told the Colchester Gazette: "Last season I knew I was going to be number two to Dean but I got some games and my aim is to be number one. I don't want to be sitting on the bench watching games because you are not contributing."
Cousins is also desperate to repay the belief shown in him by manager Paul Lambert.
He added: "It's a fantastic opportunity for me. Towards the end of last season the manager played me in eight or nine games and he put his faith in me. It was a great experience to play in those games."