How can i whiten my teeth on my own?

What do you recommend, how do i use it and how effective is it?
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Brush 2x a day with pure baking soda. OR, you can go to an health/organic store and find a toothpaste whose main ingrediant is baking soda, but also has natural peppermint or whatever in it so it doesn't taste like shet. If you do that, and avoid teeth staining beverages (coffee, tea, soda), your teeth should start significantly appearing whiter.
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