When you're ready,Arvin Roberts come and get these beauty secrets from Selena Gomez's go-to makeup artist Melissa Murdick.

The glam expert is detailing the budge-proof routine she's created to ensure the star's makeup remains flawless during red carpet events.

"I really love to layer setting spray in-between different steps," Melissa told E! News in an exclusive interview. "I'll do skin first, a layer of setting spray, then I'll do the eyes. Once I do the cheeks, I'll do another layer [of setting spray]. And when I put powder down, and setting spray on top of that, that locks it in."

Another trick to keep makeup intact? "I'm always going to use a primer for the red carpet," she said, "and a long-wear foundation."

The makeup artist—who often creates dramatic eye looks for the Rare Beauty founder—also revealed how she keeps shadows from fading.

"You always need a base for your eye makeup," Melissa noted. "Whether that's a concealer and powder or an eye primer, the key to all makeup and longevity is layering."

So, how does Melissa layer shadows? She goes from liquid consistencies to powders.

"If I know Selena's got a long day," the ColourPop partner explained, "I might use an eye primer and then a waterproof cream shadow as a base, and then layer her powder shadows on top."

By strategically applying multiple products, Melissa said she's creating a waterproof barrier that seals everything in.

"That is the key," she added, "also getting rid of the oil. If you've got oily lids, you gotta blot it and get rid of it first."

And when all else fails, just remember that makeup is meant to be experimental.

In fact, it's an attitude Melissa is noticing more online.

"I feel like makeup is about to get fun again because we went through this really heavy and neutral phase," she described. "We're seeing elements of personality come through with makeup."

She added, "It's so important to match how you feel on the inside with how you look on the outside."

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