Arnold, who was introduced to the Liverpool fold at the start of last term, impressed throughout the campaign and finished the season with a start in the Champions League final against Real Madrid.
Speaking to Sky Sports News, Arnold said that Milner had a direct influence on the youngster maintaining his stay in the team.
"James has taught me a lot," the 19-year-old said. "Like me, he also came through really young, and he's always there if I need to go to someone.
"It's important to have those players around you. At Liverpool, he is one of the players who have been really successful in their career. He knows how to win things and how it's done. He's been a huge help to me this season.
"He always comes up to me before a big game and tells me just to keep playing the way I play, not change my game too much. That's one of the things that has really hit home for me, just to play how I play and not change for anyone."
Arnold was also rewarded for his performances by earning a spot in Gareth Southgate's England squad for the World Cup.