Plan Your Paper
Begin by brainstorming, listing some of the ideas that come to mind as you look at the sculpture. Write down the subject, but also the emotional response you experience when you examine the piece. Then look over the ideas you have written to determine how they fit together and how you can focus your description, resulting in a more cohesive essay. For instance, for a paper on Michelangelo's "David," you might decide to have one body paragraph discussing the material and size of the work, another focusing just on the face and a third examining the body and pose. For a piece such as the Venus of Willendorf, you might instead choose to have one body paragraph about the material and another looking at how the figure represents sexuality.
Discuss the Basics
Your description should include the foundational information about the sculpture such as the material and type of sculpture. The medium might be marble or terra cotta, for instance, and the work may be a relief, a carving from a single block of material, or a casting. Include the size of the piece. Explain the depiction and any necessary information behind the scene. For example, if describing the Laocoon Group, the reader will understand the idea depicted more clearly if you explain the story of the man and his son attacked by sea serpents when attempting to warn about the Trojan Horse. If the piece uses color, discuss what you see and the impact it has.
Cover more in-depth aspects of the piece. Tell the reader about the textures: rough, smooth or jagged. Examine how the artist arranged the figures, how blank space affects the work, and how lighting might affect the look. Describe the poses the figures strike. Explain how these various elements affect a viewer's response to the piece to give a full description. If describing Michelangelo's "Pieta," for example, you could discuss the positioning of Jesus' body over Mary's lap and the emotional reaction to this arrangement and the expression on the faces.
Check Your Language
Use specific, concise language to make your description vivid. If describing "Winged Victory" -- also known as the Nike -- in your paper, you should note how the drapery folds about the figure's body. Rather than using general language, you might write that the cloth "presses" against the figure's torso. Instead of simply saying one leg is in front of the other as she steps into the wind, you could say the woman appears, from the pronounced leg muscles and folds of the cloth, to be striding into a gale -- making the description more effective.