Add baking soda, cornstarch, and water to a pot and stir together.
Place the pot on a burner over low to medium heat. Stir continuously until the mixture starts to pull away from the pot and it forms a "mashed potato" consistency.Pull the pot off the heat immediately when it reaches this thickness. Do not overcook!
Put the clay into a bowl or spread it out on a baking sheet to cool. Let the clay reach room temperature before working with it.It will take at least half an hour to cool down.
Step 2: Use the Clay
The texture of the clay should be very soft and moldable, but not sticky. If the clay sticks to surfaces, or your hands, dust the work area with cornstarch.
You can roll out the clay or form it with your hands.
Cookie cutters are a good tool for making shaped items, such as ornaments.Allow the clay to air dry for 3 to 5 days. Or bake it in the oven at 200F for 1 to 1.5 hours, flipping the piece half way through (see baking tips above).
Your air dry clay recipe is complete!
Video
Notes
If you're sculpting with the clay and it isn't sticking to itself well, wet the area with a bit of water - this will help it adhere.To store unused clay, wrap it in plastic wrap and place it inside a ziploc bag or airtight container.