The former Arsenal keeper, who joined the club earlier this month, has also claimed that he is excited to be part of the "project" at the Stadium of Light.
"It's a big positive. It looks like a new era, the beginning of a new project. I'm really happy to be involved in this project now," he told the Northern Echo.
"There are quite a few new players in and it's good that we've all come in at once at the start of something. The lads who were already here are helping us quite a lot.
"I think we've already made great progress in terms of getting to know each other and starting to form a team. In another month, we will be the team that the boss wants us to be."
Mannone has replaced former number one Simon Mignolet, who joined Liverpool earlier this summer.