You could study style for years, and still have scope to learn more. It’s an interesting topic that doesn’t always get the love it deserves, with some dismissing it as frivolous. We wear clothes everyday (although a duvet day now and then is compulsory), and wearing something you love can often change your mood. In homage to the dynasty that is style, this A-Z guide will bring you a little insider information on one of our favourite subjects, this week concentrating on all things I. Isabel Marant Isabel Marant was born in Paris to a German mother and French father. She described herself as a tomboy when speaking to L'Express about her childhood. Rejecting the French feminine fashion popular in the early 80s, Isabel persuaded her father to buy her a sewing machine which she used to create a bohemian wardrobe. In 1987, Marant was an apprentice to Parisian designer Michel Klein and in 1990 she set up the knitwear brand Twen with her mother. 1994 was the year she set up her own label and a hand-drawn star was the logo. Diane Kruger, Kate Moss and Rachel Weisz are all fans of her designs and her collection for high-street store H&M sold out in record time.   Issey Miyake Japanese designer Issey Miyake is known for his technology led designs, fragrances and exhibitions. Miyake studied graphic design in Tokyo and after his studies, he worked in Paris and New York before returning to Tokyo where he founded the Miyake Design Studio in 1970. His pleated designs were well received as they allowed flexibility of movement for the wearer and ease of production. His scent, L'Eau d'Issey, is a best-seller all over the world. The design of the bottle is based on the view of a moon behind the Eiffel Tower from Miyake's Paris apartment.  Iridescent Iridescent fabrics appear to change the colour as they hit the light and these foil-like fabrics and holographic finished are more popular than ever. When Vogue recommends it, you can pretty much guarantee that it's a good look and Francesca Burns, fashion editor at the renowned style bible says, "When hit by light, one colour becomes many, while the gauzy fabrics float about the body like a mystical glow. Take note of Raf Simons at Dior and go for a sculpted iridescent top over micro shorts." As well as Dior, iridescent finishes are popular with Alexander Wang and Christopher Kane. To get the look on the high-street, metallics, high-shine sheen and glittery gleaming looks can be found at Zara and ASOS.