I chained 220 with a 7mm hook (I always, always use a hook two sizes up for a foundation chain when I'm making a scarf - it stops that annoying curve) and then, using a 6mm hook, simply worked half trebles (half doubles US) in the back loops.
This is an Arashi Shibori Pleated Scarf made by Anne Selby. It's made up from six layers of lightweight silk and is called 'Peacock Stole'. To make the pleats Anne Selby steams and dry's the fabric. This piece stood out to me so much because it resembles peacock feathers so well. This really is a great fusion of textiles and technology because the balance is perfect.