Pet potty spots on the carpet. I use good old vinegar and baking soda. The steps are the important part. Pour enough vinegar to soak the stain and THEN add a small amount of baking soda. If you do the reverse, you will have a noisy, bubbly mess. Do it the right way, and you can hear the recipe cackling away, telling you how it is cleaning and deodorizing without leaving any residue. You need to let the spot dry for a day or two before sweeping up and then vacuuming. We cover the spot with a bowl or plate so that we don’t have baking soda kicked from heck to breakfast. You can actually see the yellow color being absorbed up into your little mountain of baking soda. Works on old stains too!