How do you make homemade soft modeling clay?

One such recipe is called "Salt dough".

Add a cup of salt in a large bowl.

Add 1-1/4 cups of warm water and mix well.

Add 3 cups of flour and mix well with above ingredients.

Knead into a ball then seal in a plastic bag and store overnight.

24 hours later you can mold anything you want.

Wait for 3 or 4 days (to make sure it's dry) before you paint.