DIY Tip Removes Cat and Dog Urine from Carpet -- Mix 1 part water and 3 parts vinegar. Spray on carpet stain. Let it soak for 30 minutes. Mix 1 cup of hydrogen peroxide, 2 teaspoons of baking soda with a squirt of dish-washing liquid. Shake well. Spray and let soak. Caution: Peroxide may change the carpet color, so this tip works best on white or off-white carpeting.