The Hollywood skin guru behind Jennifer Lopez's glowing complexion has revealed the biggest skincare sins committed by women.
Facialist to the stars Nichola Joss says we should all be leaving as much as four hours between applying different products to our faces - and warns against young women damaging their skin by wearing 'layers of makeup'.
Speaking exclusively to MailOnline FEMAIL, Nichola explains why habits like not removing your cleanser correctly, skipping toner, and applying all of your products in quick succession could be wreaking havoc on your skin.
She also spilled the secrets behind 48-year-old J.Lo's flawless complexion - which she attributes to a combination of eating well, intense exercise and a 'religious' skincare regime.
"J.Lo is very religious with her cleansing and the [face] masks she wears because she's travelling and working a lot," says Nichola.
"She has lots of massages all over her face and body, and she's really specific with hydration levels which means lots of moisturising and great anti-oxidants and copper serums."
Nichola, who has also worked with stars including Alicia Keys and Meghan Markle, also revealed J.Lo's fondness for facial massages and probiotics.
Here, she reveals the four biggest mistakes women are making when it comes to taking care of their skin - and the simple changes to your routine that will help you get a flawless Hollywood glow.
1. NOT CLEANSING CORRECTLY
"If you don't remove cleanser correctly, cleansing particles sit deep in your skin," Nichola explains.
"That will lead to congestion and cause breakouts and also an imbalance of pH levels. Essentially, you have to make sure you cleanse off your cleanser.
"In the evening I always make sure I remove any environmental grime, and then do a second cleanse to cleanse the skin slightly deeper."
2. SKIPPING TONER
"This is one of the most important elements for keeping skin clean and maintaining its pH levels," Nichola explains.
"It can also re-balance, refresh, and remove any cleansing particles that are still in the skin - as well as helping to remove cleanser."
3. WEARING TOO MUCH MAKEUP
"Nowadays, girls in their twenties wear far more makeup, layers of foundation and contouring and illuminators, and that can be quite damaging because there's quite a heavy build-up on the skin," says Nichola.
"The most important thing is to remove all of your makeup and do a gentle exfoliation. Too much makeup can cause congestion and cause breakouts."
4. RUSHING YOUR ROUTINE
"It's imperative to break your skincare regime up into stages," says Nichola.
"As soon as you get home, the first thing you must do is remove the grime and pollution, then allow your skin to optimise the heavy-working products like anti-ageing products.
"Do those first steps very early in the evening and leave for at least three to four hours.
"If they're working throughout the early evening while you're cooking or watching TV, they can work quite freely and you're still active and moving therefore your blood is circulating quite highly. That helps the function which helps efficacy of the product.
"And then, when you put an oil on at bedtime, because you've given these products time to work.
"When you massage an oil in at bedtime, it traps those products skin-deep so it keeps them working."
WOMEN'S BIGGEST SKINCARE SINS
Not cleaning properly
Skipping your toner
Wearing too much makeup
Rushing your routine