The Victoria's Secret model has revealed she enjoyed some downtime with her pretty pals after rounding off fashion month in the French capital.
After going to watch a Kanye West gig - who is the husband of Kendall's half sister Kim Kardashian West - the bevy of beauties relaxed at a slumber party before heading in their different directions.
She said: ''We actually had a sleepover. It was fun! It was a group of us - Cara, Lily, Gigi and Kendall in Paris. That's how we finished Fashion Month - our celebration. We went to Kanye's performance at the Louis Vuitton Museum, had a sleepover and then all took our own journeys.
''You find a clique of girls that you get along with and like having fun [with] and have the same focus and drive as you do, and you come together and just have fun. And we're always around each other. It's not forced - we're just friends. And [our friendship] takes away from [our] everyday schedule.''
As well as staying close to her model pals, Joan also relies on chewing gum to help her get through the month-long extravaganza and makes sure she always has a pack to hand when she walks at the Paris, New York, Milan and London events.
She explained: ''I try to have a chewing gum. It's so funny because I'll be chewing backstage and the person in lineup or the designer will be like, 'Are you chewing gum?' And I'm like, 'Yes, I am, but you will never see it on the runway!' And you have not caught me in one picture on the runway chewing because I bite down on it. I don't know if it's for tension or just so my face remains the same way, but I put it back here [points to jaw].''
The brunette beauty added she manages to stay in top shape for the shows by keeping hydrated and knowing when to say no to a party.
She explained to PEOPLE: ''Keeping a good energy is key. And you have to make sure you always drink a lot of water and you know when to rest and when to party. You can't continue to do every single night because then you're not going to have the energy to perform the next morning for a show, for a shoot. So I pick and choose where I go a lot of the times.''
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