When Camila Alves hit the The Sea of Trees red carpet in Cannes in a black lace and tulle Gabriela Cadena gown with a plunging neckline, we immediately had two thoughts. 1. Wowza, she’s stunning. 2. Isn’t she scared of a wardrobe malfunction?! So when we caught up with the actress the next day at the Magnum and BCBG lounge, we had to ask how she pulled off such a risky (but worth-it) dress.

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Turns out, alterations had to be made right before she stepped out onto the carpet. “We had to sew things into the dress at the last minute after I tried it on,” she told PEOPLE of prepping for the premiere of her husband Matthew McConaughey‘s new film. “It didn’t rip, but because it [the neckline] was so low and the carpet view is 360°, we had to make sure we had everything the right way. If I made one wrong move, I was afraid I was going to show a little more than what I wanted to. We taped it and sewed it in the back while I had the dress on to make sure it all stayed in place.”

And even though she touched down in the French Riviera for a short 24-hour trip, the star said she was armed with “a lot” of options.

“It’s Cannes, you know? This is the time to really be elegant and chic,” Alves shared. “You have to bring it. I did something different last night; I changed it up which was fun. I had beautiful jewelry that Lorraine Schwartz custom-made for the premiere.” (FYI on the jaw-dropping jewels: her diamond and emerald vintage necklace and drop earrings are worth over $1 million.)

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For Alves’s second Cannes cameo, she went for a more casual look, attending the Magnum ice cream lounge in a lace flounce BCBGMaxAzria tunic dress teamed with a chocolate-scented scarf. (Yes, you read that right.)

And because you can’t bond over ice cream without talking about summer, we asked Alves about her must-have warm-weather essentials. “Suncreen, sunscreen, sunscreen — for sure,” she said. “I have this omega oil product that I like to put in my hands and on my face. After you come out of the sun it kind of keeps everything hydrated. And drinking lots of water.”

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What do you think of Alves’s Cannes dress? What summer beauty tip do you swear by? Share your thoughts in the comments!

–Colleen Kratofil, with reporting by Whitney Little

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