Although a long bob is considered a universally flattering cut, the most flattering hairstyle for an individual generally depends on the shape of the face. The basic face shapes include oval, square, heart and round.
According to About.com, oval faces look best with styles that don't add height and, if the hair is curly or thick, aren't too blunt. Shorter hair works best for oval-faced individuals whose faces appear long.
Square faces look great with textured styles, such as curly or chopped cuts that soften the jaw or draw attention away from it, whereas individuals with heart-shaped faces should consider styles that draw attention to their cheekbones and eyes rather than to their chins.
Round-faced individuals often look best with longer hair. They should avoid curly styles or styles that exaggerate their faces' round shape.