Air dry clay is a type of modeling clay you can use to make dolls, plaques, jewelry or anything else you might typically make with kiln-fired or baked clay. There are several different brands of air dry clay available commercially, with sculpting and crafting recommendations that vary based on the type of product you select.
Natural Air Dry Clay
Crayola offers a natural white earth clay that you can mix with water to soften and press into molds or shape with a variety of clay tools. You can also paint or carve Crayola's air dry clay after it has hardened.
To join molded clay pieces together, Crayola recommends making slip, a mixture of water and clay with the consistency of heavy cream. You'll need to roughen up the sides of both objects where you plan to attach them, then apply slip like glue and press the pieces together.
Similar to porcelain clay, Crayola's natural clay may be thrown on a potter's wheel, but do not fire it or use traditional glazes. You'll need to store any unused clay in an airtight container, but you cannot store it if you've already added water.
To make an object with natural air dry clay, add water in accordance with the directions on the label and manipulate the clay until it is malleable. Create the shape of your object with your hands, a mold or by using clay tools like a potter's wheel or rubber stamps. Crayola recommends that you keep your structures at least 1/4-inch thick or the material may crack. When your project is complete, let the clay air dry for at least 24 hours. You can also create a generic shape close to your desired object, let it dry and then carve the dry clay to complete your project.
Air Dry Polymer Clay
Makin's air dry polymer clay is non-toxic, but does have some acidity when it's wet. This clay comes in a variety of colors, but the manufacturer suggests that you can mix it with acrylic paints to create even more colors. This air dry polymer clay will dry after being exposed to air for 24 hours, but you can keep it moist by covering it with a wet towel. You can also brush a small amount of water onto the surface if you'd like to smooth the texture or make the clay more pliable.
To make a pendant with air dry polymer clay, knead the clay to soften it and then press it flat with your hands. Roll the clay through a pasta machine set on the highest setting to create a clay sheet with a uniform thickness. You can use a cookie cutter or a clay knife to outline the shape of your pendant. Roll a small amount of clay into a snake with the palm of your hand. Twist the roll and wrap it around the perimeter of your pendant. Press the clay together underneath to attach the pieces together. Insert flat-backed rhinestones, cabochons or beads to decorate the face of the pendant. Insert a knitting needle at the top of your pendant to make an opening so you can hang it on a necklace. Let the clay air dry for at least 24 hours.