Whitening Teeth Techniques?

I don't have enough money to go to the dentist and pay all that money to get my teeth whitened. Does anyone know of any other products that you can buy to whiten your teeth? Thanks guys!
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You should consult your dentist before whitening to make sure that you don't have any cavities or any other limitations that would compromise your tooth whitening results. To determine the initial color of your teeth, compare them to a sheet of bright white computer paper held up to your mouth. The degree of whiteness that can be achieved depends on what color the teeth are to begin with and the source of the discoloration. Brown or yellow teeth (often the result of superficial staining caused by smoking, coffee, and tea) will usually get whiter. Gray teeth (caused not by stains but by pigment deep inside the tooth) will lighten less, sometimes not at all. Avoid things that stain teeth like coffee, red wine and cigarettes. Follow the "white teeth diet" Drink white wine instead of red wine, cappuccino instead of espresso, and grapefruit juice instead of cranberry juice. Tooth bleaching gels containing carbamide peroxide (10 - 22% solution) and glycol or glycerine and can be purchased over the internet. Hydrogen peroxide is also used. The higher strength solution and longer bleaching time produces faster results but may cause increased sensitivity. Commonly, your teeth or gums will become sensitive while using products containing peroxide based gels but it is not harmful. You can minimize sensitivity by using a toothpaste with fluoride and 5% potassium nitrate (Crest Sensitive, Sensodyne.) Also you can reduce usage time and/or frequency until the sensitivity subsides. Tray-less Whitening systems include Crest Whitening Strips or a paint-on gel like Colgate Simply White There are 2 kinds of at-home-tray whitening systems which you use with a bleaching agent: ----> A custom-fitted bleaching trays is fabricated by a dental lab, from a kit which you order on the internet and mail to a dental lab. -----> A "boil-and-bite" tray made by you The at-home bleaching tray methods require a fitted mouth tray (bleaching tray) to hold the bleaching gel against the tooth either overnight or hourly depending on the strength of the bleach dispensed. Formerly, only a dentist could fabricate the bleaching tray. Nowadays, custom-fitted trays can also be ordered via the internet. You take the mold of your teeth and mail the molds to a dental lab who fabricates the trays and mails them back to you. in a couple of weeks. Alternatively, the boil-and-bite trays are thermoform trays placed in boiling water for a few minutes to soften and then mold against your teeth yourself. They may be bulkier and not fit as well. Tooth bleaching/whitening gel does NOT bleach (or harm) bonding, caps, crowns, bridges, fillings or any other artificial dental work. You may have to have the dentistry redone in order to match your new white teeth. Prior to Treatment Brush and floss just prior to bleaching your teeth. Whitening gel is the most effective with clean teeth Check for a comfortable fit of the trays first without any beach. Make sure that the bleaching trays are clean and dry before applying the whitening gel. Moisture reduces the efficiency of the whitening gel and slows down the whitening process. Keep bleaching gel out of reach of children. Do NOT use if pregnant or during nursing. Do NOT smoke, drink or eat while bleaching your teeth. See your dentist regularly to check for dental problems.
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