There are two ways: swishing it around your mouth or mixing it with baking soda and setting it on your teeth as a paste before rinsing.

Using hydrogen peroxide as a rinse:

  1. Mix equal amounts hydrogen peroxide with water, such as 1/2 cup to 1/2 cup.
  2. Swish this mixture around your mouth for about 30 seconds to 1 minute.
  3. Stop and spit out the solution if it’s hurting your mouth and try not to swallow any of the mixture.

Using hydrogen peroxide in a paste:

  1. Mix a few teaspoons of baking soda in a dish with a small amount of peroxide.
  2. Start to mix the soda and peroxide together with a clean spoon.
  3. Keep adding a little bit more peroxide until you get a thick — but not gritty — paste.
  4. Use a toothbrush to apply the paste to your teeth using small circular motions for two minutes.
  5. Leave the paste on your teeth for a few minutes.
  6. Then, thoroughly rinse off the paste by swishing water around your mouth.

Make sure you remove all of the paste before moving on with your day.