James came off the bench as Man Utd led Chelsea 3-0 and he scored just seven minutes later to crown a memorable first PL appearance.
"When you come to a new club, especially as a winger, you want to contribute to the team with goals and assists, and to get that goal really has helped me."
The 21-year-old says he has benefited from seven consecutive starts after his opening-weekend debut.
"When I joined that's what I wanted to do," he said.
"I wasn't coming here just to be a squad player, but for the gaffer to believe in me and play me from the start, that's something I want to continue to do."
James adds that the togetherness within the United squad has made his adaptation to the top flight seamless.
"They've all been great," he said. "I haven't been here for long but I've made some great friends already and that's so important when coming to a new club because you feel a bit intimated at the start, playing at such a big club.
"Everyone has been great with me and I really thank them for that."