The Princess of Wales is a lifelong fan of liner, and her kohl-rimmed eyes have been her makeup signature since the world was introduced to her more than two decades ago. Over the years, Kate has adapted her eyeliner to suit her face, and has tweaked it once again with a placement described as ‘perfect’ for mature eyes by legendary makeup artist Laura Geller.

The Princess treated us to a close-up look at her latest makeup evolution on her most recent royal engagement, to the Isle of Bute in Scotland. Not only did her eyeliner stand up to a windswept day and a vigorous game of hockey, it showcased a clever ageless technique that all women over 40 should take note of: the 'first lash' rule.

kate princess wales eyeliner lash
Samir Hussein
Kate gave us a close-up look at her perfectly shaped eyeliner

It’s a trick that was highlighted to us earlier in the week by MUA Laura, who is in the UK to launch her eponymous mature beauty brand in Boots. And by wonderful coincidence, up pops Kate to give us a masterclass of the theory in practice.

kate princess wales eyeliner lash
Samir Hussein
Taking liner along both the top and bottom lash is the key

‘I always say you're naked without eyeliner,’ explained Laura, who started her career on Broadway and worked with icons such as Audrey Hepburn and Liza Minnelli. ‘As you get older, you lose shape in your eye. You’re lining it to put that shape back.’

Kate provides a textbook example of Laura’s recommended technique for this, which centres on her ‘first lash’ technique. ‘You want to start your eyeliner at the very first lash, top and bottom,’ Laura told us. ‘Don’t start your liner half way along. A lot of people do that, especially at the bottom, but it’s not balanced when it’s stopping halfway.’

kate princess wales eyeliner lash
Mark Cuthbert
Kate’s look really shapes her eye

The Princess of Wales has nailed the most flattering, ageless liner look by creating the same shape top and bottom, but keeping the pigment intensity higher on the top lashline for a look that automatically lifts as well as defines.

‘For a perfect shape, you want eyeliner darker across the top, touching the lash, and softer on the bottom lashline,’ said Laura, who has just introduced her eponymous beauty brand into Boots.

kate princess wales eyeliner lash
Samir Hussein
Kate looking beautiful on the Isle of Bute
kate princess wales eyeliner lash
Samir Hussein
The right eyeliner will stand up to all activities

To avoid overloading the eye, and visually dragging it down, Laura advises taking your first lash as your marker, but starting very delicately there. ‘First lash, thinner, thinner, thinner, and graduate it to be a little thicker at the outer lashes,’ she told us. ‘It should be the same width on top as it is on the bottom, always softer underneath, and then a stronger line on top. Don't be afraid of doing dark charcoal, dark brown, black or even a dark navy which makes the whites of the eye brighter.’

kate princess wales eyeliner lash
Mark Cuthbert
Kate always keeps her beauty look fresh

She likes a kajal formula which gives a short window to soften and blend, then sets tight. Her own Kajal Longwear Eyeliner is impressively waterproof (our back-of-the-hand swatch was still sitting fast the next day, and needed a good rub to shift!)

Laura Geller Kajal Longwear Eyeliner

Kajal Longwear Eyeliner

Laura Geller Kajal Longwear Eyeliner

Credit: Boots

As it happens, Kate’s latest makeup look follows Laura’s key overall rule for mature makeup. ‘I have a philosophy, it's called the Three Es: eyebrow, eyeliner, and eyelash,’ she told us. Eyeliner and mascara are usually in most mature women’s toolkit already, but it’s brows where we are most likely to be missing a trick, in Laura’s opinion.

kate princess wales eyeliner lash
Mark Cuthbert
Kate’s look combines the Three Es: eyeliner, eyelashes, eyebrows

‘I don't care what anybody says, you need to define your eyebrows,’ Laura told us. ‘When you fill them in, it adds shape to the face. And a strong eyelash opens the eye. So, just remember those three Es, those are the three things you always have to do.’