Sienna Miller and her sister Savannah made their London Fashion Week debut yesterday

The siblings - wearing short black belted dresses and thick black tights - soaked up the applause of the crowd viewing their Twenty8Twelve collection of shoulder-padded shirts, tuxedo jackets, sparkly dresses and pale macs.

At times, Sienna appeared “giggly and embarrassed” by the attention from the audience, which included Courtney Love, Kanye West and Twiggy.

The collection mixed Sienna’s punk and boho tastes - patterned dresses were teamed with leather biker jackets - and Savannah’s more conventional style, apparent in the floral-print tunics and cashmere knits.

Speaking before the show, Sienna said: “Put them together and it says London cool.”

Nicole Farhi also showed on the catwalk yesterday, and the veteran vowed too “shake things up” after admitting any designer can “get stuck in a rut”.

The fashion-forward show was opened with rainbow tweed skirt suits and trench coats, and prominently featured an elegant 40s-style silhouette, showcased perfectly in slim sequinned pants, boyfriend blazer and a dazzling claret pea coat with oversized fur sleeves.

In a modern twist, the designer mixed up several styles, teaming woollen knee socks and heeled brogues with pencil skirts and wide shouldered, 80s-style mohair knits. Oversized leather clutch bags were shown with trench coats and crystal details.

Earlier in the day, a range of famous British models wowed a star-studded audience at PPQ’s show.

Daisy Lowe, Pixie Geldof and Alice Dellal showcased a fun collection of vivid rainbow colours and broad stripes as celebrities including Girls Aloud’s Nicola Roberts looked on.

Betty Jackson opened day three of the event – which is celebrating its 25th anniversary - with what has been hailed her best collection in years.

Using luxury fabrics including silk and velvet, the blue, yellow, chestnut and teal collection delighted, with a high-waisted yellow anemone print coat and brown silk spot dress with ruffles and full sleeves marking particular highlights.