The Big Brother winner, who has become the new face of the clothing line, said that she didn't mind to be asked to front the campaign.
"No, it was really nice," she told Now magazine. "I never thought I was model material.
"Curvissa's clothes are fantastic, though. They range from size 14-32 and they're all really flattering. I hate the fact that lots of plus-size clothes are just baggy T-shirts that say: 'I love chocolate'. Who wants to wear that crap?"
She added that she is currently not on a diet but is trying out a new exercise regime in order to "tone up".
"I'm toning up. I don't want to lose my curves. I look better curvy. I'm doing lots of muscle work, walking and drinking less wine.
"I don't have a personal trainer but I follow exercise DVDs like Coleen Nolan's after a few glasses of wine with a mate for a laugh - so I'm not sure how useful it is!"
Gibson recently said that she intends to lose weight after seeing bikini photos of her in The Sun. She also revealed that she had lip enhancement surgery earlier this week.
Watch Josie Gibson chat to Digital Spy at the 2011 Big Brother auditions below: