When we use our dinnerware regularly, there are chances of stains and scuff marks to accumulate over time. But following the right cleaning process will keep your porcelain dinnerware free from all kinds of stains. Prepare a mixture of 2-3 tablespoons of citric acid with your dishwasher detergent. Let your stained dinnerware soak in this solution for a couple of hours. For tough stains, soak in hot water. Wash and rinse thoroughly.