They both have their own, unique techniques for getting that subtle, lit-from-within glow.
For Lou, it's all about the Tanologist Self-Tan Water.
"I use the water on makeup brush on my face before bed," she says. "So, take a big foundation brush or even a bronzer brush, brush it around so that when you wake up, your face is really glowy!"
Meanwhile, Lottie swears by the Tanologist Face and Body drops, especially when it comes to travelling.
"When we're on a flight, we just take our makeup off, add a few drops into our moisturiser or serum and by the time we land you've just got a nice little tan," she says.
"They makes us look alive so we can learn to take pictures straight away!" Lou adds with a laugh.
The furthest place we might be travelling to RN might be our fridge, but we're defs stealing that hack for our iso glam!
For more of Lottie and Lou's tanning and business tips, as well as the tea on what it was like to tour with One Direction, tune into the Beauty Boss podcast below!