Sculpting the Details for a Small Clay Horse Head Sculpture:
I'm now going to start on the fascial details. Using your reference materials, add clay to build up the features. Use slip to add the clay, and use a wood modeling tool for these smaller details. Get one side laid out and check it from all angles to make sure that it looks right.
Use the wood modeling tool to shape the rough placement of the clay, smoothing it as you go. Once you have one side fairly laid out, start on the other side, comparing it to the first side from all angles as you go.
Check the angles repeatedly, but keep in mind that no face, human or animal, is ever completely symmetrical. You do not need to aim for perfection because it will make the sculpture look fake. Another trick I use to make a sculpture look more real is to add bulk. If you create a sculpture too thin, it will not have enough substance. Since sculptures are not moving and breathing you need to capture your subject's strength and characteristics, and sometimes even exaggerate them a bit. Adding musculature and a slight bit of girth will help to add a sense of life to your work.
Once the face is fairly completed, add the rest of the details such as the mane and, if you want, a bridle. On this sculpture I decided to go with a western-style bridle and a wild mane to give it a sense of movement. I usually make bridles by rolling clay out into thin cylinders and then, using slip, smoothing them down onto the sculpture. When making the mane, remember that hair has bulk. If you just carve it into the neck it will not look real. Add slivers of clay and then, using the wood modeling tool, add texture to the mane. Remember also that strands of hair, though they look like they are going the same directions from a distance, travel in sporadic paths. Small details like hooks and metal accents make the bridle look more realistic.
When the sculpture is completed except for smoothing out the surface, use a needle tool to poke holes through the larger muscle masses, straight through the clay until you reach the open cavity inside. This "air-venting" will open up any air pockets that may have been created, venting them into the inner cavity during firing. Smooth the holes back over on the outside, and finish smoothing the surface of the clay.
After the sculpture is completed, leave it uncovered to dry, but carefully wrap plastic around the reins (if you made reins). The reins, because they are so thin, will dry before the rest of the sculpture and shrink to their permanent size. When the rest of the sculpture dries and shrinks, it will break the reins. Keeping the reins covered until everything else dries will help prevent the reins from being damaged.