How can I get whiter teeth?

I want to whiten my teeth. Any natural ways to do it at home. Without like Crest Whitening Strips?
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you need: 1 ripe strawberry 1/2 tablespoons of baking soda Steps 1.brush teeth (1 minute) 2.mush strawberry & mix with baking soda 3. brush teeth for 30 seconds 4. Do this for once each week
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