The singer-and-actress - who joined Randy Jackson on the judging panel along with Aerosmith star Steven Tyler earlier this year - found it "entertaining" when people at the recent Los Angeles auditions performed their versions of her hits, but has advised hopefuls on the star-search show to try a different approach.
She said: "It was cute, super entertaining and flattering, but no.
"I think everyone tried to be as honest as they can without breaking anyone's spirits. They know we're not out to cut them down or make a joke of them. We're trying to mentor them to the next step."
However although some hopefuls have failed to impress, Jennifer admitted she is excited about the talent so far this season - even though the lengthy audition process is taking its toll.
She said: "We've put a bunch of people through - probably more than they have in the past.
"We have about 15-20 real superstars, people who could be recording artists.
"I've cried. We get a lot of elation when we put them through and devastation, almost, when they're not. But it's been a ball."
The 41-year-old star - who is known for her sense of style - has also promised to wear some amazing outfits on the show.
Speaking at a press conference for the show, she said: "Look, I'm just going to be me. Every day that's something different. I like getting dressed up. That's not going to change for this show."