The actor - who plays an exotic dancer in director Steven Soderbergh's new film - explained that he learned a great deal from his stripper-turned-actor co-star Channing Taum.
"I've never danced in my life [before Magic Mike]," Pettyfer revealed to E! News. "I can't put one foot in front of the other, let alone shake it... But you know what I learned - apart from Channing's amazing dancing - the funnier, the grimier, the dirtier it is, the bigger reaction you get."
Pettyfer went on to describe the anxiety of stripping down before Soderbergh's camera for the very first time.
"When you see me come out for the first time with the song 'Like a Virgin' is the first time I had ever performed any dance, it was the first time I had ever really been on stage in front of an audience," he recalled.
"I've always been able to hide behind a camera. [Here], all the reactions you get are genuinely the same reactions you see in the movie because Stephen shoots the audience at the same time he's shooting you, so you really got to impress them."
Petty previously described that first stripping routine as highly embarrassing.
Magic Mike opens in the US on June 29 and July 11 in the UK.
Watch a red band Magic Mike trailer below: