You should consider shape when buying a diamond ring because it will affect how the ring looks on your finger. Women with shorter fingers should try on elongated styles such as a pear, oval, or marquise, and avoid wide bands that give the illusion of even shorter fingers.
Square shapes such as radiant and princess are best for women with long fingers as they make them appear shorter.
Women with larger hands may want to avoid very slender, delicate ring settings and narrow diamond shapes like the emerald or the marquise, as they will not look proportional. Heart and round shapes are better for larger fingers, and likewise not flattering to thin fingers. It's important to try on a variety of styles for contrast, even if they aren't your first choice.