First, pour one cup of white vinegar all around the inside of the toilet bowl, making sure to cover the stained spots. Give it a quick swirl with the toilet brush to spread it evenly. Next, sprinkle one cup of baking soda over the vinegar. Then, slowly pour another 1 to 2 cups of vinegar on top. You’ll see the mixture start to fizz and foam right away.
Now, just let it sit for at least 30 minutes. For really tough stains, you can leave it for an hour or even overnight. After the time is up, give the bowl a light scrub with the brush and flush. You’ll be amazed to see a sparkling clean toilet, with all the stains gone!