Selling your store to the fashion crowd requires a ­trend-obsessed mindset, a willingness to change (your cases), and a way with propsYou’ve already claimed your region’s fine jewelry consumers. Wouldn’t you like to lure that lucrative yet fickle shopper, the fashionista?After all, price is no object when she’s on the prowl—which is to say always—for the latest and greatest. It’s no exaggeration to suggest that she’ll sacrifice anything—budget, space… Who cares if she has to store Manolo Blahnik stilettos in her oven and Alexis Bittar ­shoulder-dusters in her bathroom?Nor should you. Follow our merchandising guidelines, erring on the side of fashion-forward, and she’s yours for the taking.Keep Up With the TrendsRobert Tateossian entertains editors during London’s men’s fashion week.Choosing to be à la mode is easy. Succeeding is another. Even designers look t