The veteran actor, who stars in new horror film The Wolfman, also claimed that American performers "didn't try to do too much" in the past.
Hopkins told Parade: "It's very easy. If you'd asked John Wayne he'd have probably said, 'Well, you just go to Monument Valley and get on a horse'. Acting is very, very simple.
"That's the trick great American actors have had. John Wayne didn't have to act, he just rode in. Gary Cooper, all those guys were smart. They didn't try to do too much."
The 72-year-old added that he thinks that young actors are "very insecure" and offered some advice for up-and-coming stars.
"I say just get up and do it. Don't do all this preparation. Don't waste time worrying about it, looking over your shoulder.
"But when you're a young actor it's not easy to do that because you always want to analyse because you're very insecure. If I could revisit my past, I would say to myself, 'Don't think too much, just get out there and do it'."
> Anthony Hopkins: 'Hollywood can be madness'