As you do when you're an A-list celeb.
The hot duo were aboard a luxury yacht, but soon plunged in for some respite from the heat.
Surprisingly, Cara looked far from high-fashion in knee-length red shorts and a plain black bikini top, while Selena wore a stunning white one-piece as she pulled off several modelesque poses while on board.
The pair later changed - Cara into white dungarees and a stylish royal blue hat, and Selena into a chic monochrome outfit.
We'll trade lives with you anytime, guys!
