I'm going out tonight, dressed as an hourglass. Not in an hourglass costume, I'm talking about one of the six basic silhouettes. Most advice in how-to-dress books would be unnecessary if women learned to dress in the silhouette that most closely matches their own body-type. The six basic shapes are hourglass, rectangle, oval, figure-eight, triangle, and wedge (inverted triangle); they are determined by the line of the shoulders (straight or sloped), how the width of the shoulders relates to the width of the hips, and whether or not the waist is visibly smaller. Sketch it out.
To study this subject in depth, I recommend the excellent book The Triumph of Individual Style
, by Carla Mason Mathis and Helen Villa Connor.
The good news: there's really no such thing as a pear-shaped woman. She's a triangle, wearing the wrong outfit.