Rule #3: Don't be cool
Cool is not the end goal. Dressing in black doesn't mean you have better ideas. It becomes the mask that many hide behind to avoid being truly original. Resist the urge to dress like the "creative's" within your job category (e.g. black for designers, jeans/t-shirts for web types, etc). If your willing to compromise to dress like others, are you willing to compromising your vision/ideas/creativity?
Be honest .... Are you spending time looking at your competitors and focusing on how to create "cool" products/services like them? Who owns the definition of cool? If you are focusing on the others to define cool, then its obviously not you.
Here is a radical idea ... Why not try being un-cool? You might find yourself defining the new hit thing.
Cool is conservative fear dressed in black.