What do you use if you don't have self raising flour?

Out of cornstarch == 1 tablespoon cornstarch..... use 2 tablespoons of all purpose flour

Out of self rising flour.....make your own

1 cup of self rising flour......... you will need 1 cup flour, 1 teaspoon baking powder, 1/2 teaspoon salt and 1/4 teaspoon baking soda