What i should use to make my teeth whiter without going to the doctor?

Nothing: You should always make sure you have an exam by a dentist before trying at home bleaching. That being said the home use strips aren't too bad. When you see a dentist for bleaching you are getting guidance & not just a product.(i'm not in favor of home extraction kits either. :-) ).

Over the counter : You should always have a dental exam and cleaning before using at home bleaching products, but assuming your mouth is healthy and your teeth used to be whiter and have just stained over time than try using crest whitening strips. My patients seem to get the best results with that product. Still the best way is to have custom fitted bleaching trays and professional strength solutions (stronger).

Store-bought whiten: Some products in the store can whiten teeth but not as safely or thoroughly as professional applications. Try them and then have a professional approach as you can in the future.

Teeth whitening: You can use over the counter tooth paste or crest 3D whitening strips or pens. However, they are not so effective and/or stable. OTC bleach and whitening tooth paste could be used as a supplement only. A professional teeth whitening, followed by home whitening system with custom trays for the long term effect. You will be very happy with the results.