Combine 1/2 cup flour and 1/2 cup cornstarch in a bowl.

Add enough water to the flour and cornstarch to form a smooth paste.

In a separate pot, bring 3 3/4 cups of water to a boil.

Dissolve 1 cup of salt in the boiling water.

Gradually add the boiling salt water to the flour and cornstarch paste, stirring constantly to avoid lumps.

Cook the mixture over medium heat until it becomes clear and thickened, approximately 10-15 minutes.

Remove from heat and let it cool completely overnight.

Once cooled, gradually add 6 to 8 cups of flour to the mixture.

Knead the mixture until it reaches the desired consistency for potter's clay.