Sex, drugs and floral fabrics: Celia Birtwell relives her wild times – and wilder outfits – with Ossie Clark

<p>They dressed – and partied with – the innermost in-crowd. As a swirling new show celebrates their fashion creations, Birtwell recalls her happy days with Clark and her sorrow at the loss of David Hockney</p><p>In the mythical age of bohemia, the psychedelic decade between Mary Q