How to whiten my teeth?

I have yellow teeth and am only 15 people always ask me why I don't smile and it's because of that For a couple of years I never used to brush my teeth and now I regret it but I want to whiten what would you recommend? if there are any good whitening kits please recommend them p.s. I brush my teeth everyday now
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Mix baking soda with just enough peroxide to make a paste. Much cheaper than store bought kits and just as effective.
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