One way is to look at customer and consumer trends (lifestyle, workstyle, fads, demographics) to anticipate how to interact with emerging trends.
Another way is by anticipating demand. You should pay attention to what people are looking forward to in the near and not to distant future. Authors can use this information to decide what to write about and companies and brands can decide what to manufacturer and market.
Take a look at what’s powered by Trendrr a New York-based business intelligence platform for digital and social media.
NY Magazine Anticipation Index (what people are most excited about in entertainment and pop culture)