The 21-year-old returned to the side in Thursday's 1-0 win at Liverpool, helping the team keep a third clean sheet in a row. His new wing-back role has come about following Tuchel's successful switch to a back three and he feels the players have done well to adapt so quickly.
"The style of play that he's brought in was evident and clear for us to understand," he told the club's website.
"The more we play together, the stronger we will be. Game by game, we will get better and build together."
It has been six weeks since the German arrived at Stamford Bridge, during which time the Blues have remained undefeated in all competitions and conceded just twice in 10 matches.
"He is very funny and very passionate because he wants to win," James revealed.
"He wants the best for his players and his team, and that shows when he's on the sideline kicking and heading every ball. Everyone gets on well and it's a great group."