You can make baking powder yourself using other common kitchen ingredients.
Using Baking Powder
Baking powder produces bubbles that cause baked goods to rise by making carbon dioxide gas as soon as the dry and wet ingredients are mixed. Ensure success by preheating your oven. Don't overmix your ingredients or wait to bake your recipe or the bubbles may have a chance to dissipate, causing your recipe to fall flat.
Storing Homemade Baking Powder
Homemade baking powder will clump together if it isn't used right away, but you can prevent this by adding 1 teaspoon of corn starch to the baking powder mixture. Store the baking powder in an airtight container. Commercial baking powder preparations often contain undesirable ingredients (such as aluminum compounds). By making your own baking powder, you'll have complete control over your ingredients. You can test
the baking powder before using it to make sure it is still fresh.