Besides her treatments, they all rate Retinol Reform, the cult classic in her eponymous skincare line which found fame on Snapchat last year thanks to Kim Kardashian rightly raving about it.
Darden says the game-changing anti-ager was "specifically formulated as a gentle alternative to retinol products on the market that were proving too harsh for my clients' skin."
Think you can't even tolerate a gentle retinol? Well (and you heard this here first), Darden tells us she's about to launch a Texture Reform Serum to complement the existing Retinol Reform. "The Texture Reform will have the same amazing benefits, but will be specially formulated for those with sensitive skin." Interested.
But while retinol is her first love when it comes to skincare ingredients, she has other tricks up her sleeve. Water being one. But not in that my-skin-looks-so-great-because-I-drink-eight-glasses-of-water-a-day way – because we'll never buy that.
"Drinking water doesn't hydrate the skin", Darden confirms, "but it is the easiest health tip I can give my clients.
"It's amazing for digestion and helps flush toxins from the body. I always stock up on FIJI Water at home and for clients at my studio. I even keep a bottle with me all day and I encourage my clients to do the same."
Darden says she drinks about two litres of water daily, or "a bit more if I'm going to have a cup of coffee or a glass of wine". Which she does with her famous friends (according to Instagram).
A fan of the 'less is more' approach over an eight-step routine, Darden's regime is straightforwards. "In the morning I use a gentle cleanser followed by an antioxidant [serum] and a sunscreen. I never leave the house without first applying an SPF 30. In the evening I cleanse, apply Retinol Reform, and moisturise. I use a light chemical exfoliant weekly."
She recommends the same simplistic skincare to her clients (tweaked for their skin type and concerns, naturally). Red carpet prep requires more effort, though.
"I typically recommend a facial two weeks before a red carpet event. Clients come in for a peel the week of an event (or sometimes the day of, depending on their skin type). I always avoid extractions immediately before an event so as not to irritate the skin."
Retinol, water, facial. Sounds doable to us.