Sienna Miller just traded in her signature waves for a heatwave-proof bun - and it's so easy to try

Sienna Miller pictured at the Serpentine Summer Party 2026, smiling with blonde hair pulled back into a ballerina bun and wearing a fur-trimmed jacket.

If you're like us, you'll be doing anything to prevent your hair from sitting at the nape of your neck during the heatwave.

In temperatures like this, strands of hair sitting against clammy skin can lead to sensory overload – not to mention, any sweatiness can leave your tresses oily, even if they've just been washed.