If you are using this as a dry powder: Omit the water. Then pour all dry ingredients into an airtight container. Consider adding in a bag of uncooked rice in a clean cloth to help keep the dry mixture from clumping. Add one tablespoon of dry powder mix to your dishwasher dispenser. Also use vinegar or jet-dry in your rinse dispenser too.
If you are making tabs: Add water, wait for fizzing to stop (about 1-2 minutes). Then add your mixture to ice cube trays, pressing with your fingers or back of a spoon. Let dry in a warm and sunny spot for 24 hours or till completely dry. Remove and add to an airtight container. Add one tab to the dishwasher dispenser. Also use vinegar or jet-dry in your rinse dispenser too.