Let the dress supply the starting point for evening. Sandro Qatar's evening dresses can work with a simple bag as the only noticeable accessory, or with footwear that adds another point of contrast below the hem. Judge those proportions together before adding further details.
The amount of contrast should suit the dress and the setting, not a fixed rule about evening outfits. A restrained finish can leave the main silhouette clear, while one chosen accent gives it a different mood. Imagine more than one styling arrangement when deciding how a dress will fit into your occasion wardrobe.