From boho chic to British “cool girl,” Sienna Miller has been a beauty and fashion muse for more than two decades—and her latest role gives fans a new look to study and steal. In HBO’s new legal drama War, Miller plays Carla Duval, a movie star navigating a highly public and increasingly contentious divorce from British tech entrepreneur Morgan Henderson (Dominic West). Carla’s life may be unraveling, but her look never does. Even in her most vulnerable moments, she maintains luminous skin, polished blonde hair, discreet eye definition and a neutral lip.
The look was designed by the show’s hair and makeup designer, Tara McDonald, who describes it as “a kind of understated elegance that feels innate” rather than constructed. “Even in her lowest moments there is still a sense of control in how she presents herself,” she says.
Ahead, McDonald shares the products, on-set tricks and simple steps behind Miller’s look—including an overnight shortcut to her soft waves.
The Overnight Hair Trick
Carla’s soft, polished waves don’t always require a lot of work. “To achieve Carla’s waves, try sleeping with a loose plait in your hair, as this way you may get away with not having to use a hot tool,” McDonald says. “Sienna did that from time to time!”
The other key to the look is healthy hair to begin with. “Focus on condition by having lots of treatments, and get a great colorist!” she says. On set, McDonald used Oribe and Shu Uemura on Miller’s hair.
Building the Look
McDonald started with skin prep. “I focused on luminous and beautifully hydrated skin,” she explains. “For makeup, we settled on subtle definition around the eyes and a neutral lip that enhances rather than transforms her natural features. Nothing feels overly done, but every detail is considered.”
The hair follows the same philosophy. “Polished but never rigid, soft natural movement and a healthy sheen,” McDonald says. “It was important that she looked like someone for whom elegance is second nature, even when things are falling apart beneath the surface.”
Two Sides of Carla
McDonald created two distinct looks for the character—a polished “on-duty” look for court and a softer at-home version. “The contrast was to show the difference between the person Carla presents to the world and who she is when nobody is watching,” she says.
Both looks began with Miller’s own signature makeup. “For the court look, I elevated it, keeping the skin fresh and luminous but adding more definition around her eyes and more color on her lips and cheeks,” McDonald explains. “It was important that she looked confident, composed and in control without the makeup ever feeling too done.”
At home, the approach was simpler. “I would strip everything back. The skin feels more real, the eyes are less defined and there’s a more relaxed, lived-in quality to the makeup. A bare elegance,” she says. “The idea was to make subtle changes to her signature makeup that could reflect where Carla was emotionally.”
The Products
On Miller, McDonald used Chantecaille, Haus Labs and MAC makeup, along with Charlotte Tilbury lip liners and lipsticks.
“I have been working in film and television for many years now. I’ve developed an instinctive understanding of which products perform beautifully on camera and withstand the demands of a long filming day,” she says. “For War my choices were highly considered. I wanted the makeup to feel natural, authentic and effortless—it’s quiet luxury!”
How to Get Carla’s Look
According to McDonald, the key is restraint. “Don’t overdo it. Spend time on skin prep,” she says. “Use lightweight products that allow the skin to breathe and only use foundation where required. It is not necessary to completely paint your whole face.”
Her step-by-step:
Eyes
“Define the eyes using a soft pencil (my favorite is the Victoria Beckham Kajal liner) and then blend the line with a soft brush.”
Brows
“Brush your brows and fill them in, but naturally.”
Lips
“Choose a lip pencil close to your own tone and try it with a hydrating balm.”
Cheeks
“Pop a cream- or gel-based blush high up on the cheeks and across the bridge of your nose.”
Grooming the Men
For the male cast, the goal was makeup the viewer would never notice. “My approach to male grooming is to always keep the skin looking as natural and believable as possible. It should be almost invisible,” McDonald says. “I’d hate for the audience to spot makeup on the men!”
Her go-to: Chantecaille’s Just Skin Tinted Moisturizer ($72). “It gives a beautiful, lightweight finish that subtly evens out the complexion without looking like foundation,” she explains. “It allows the natural texture of the skin to show through, which is important when filming in high definition. I work with very sheer layers, only adding coverage where it’s needed rather than covering the entire face.”
For Dominic West’s Morgan Henderson, McDonald used a mix of shades darker than his natural skin tone. “I wanted him to have an effortless patrician glow,” she says.
Ultimately, McDonald says, the overall approach comes down to one idea: “It’s about looking impeccably put together, but without looking like you’ve tried too hard.”