What is the best way to get very white teeth? i brush them every morning and night, and they never seem to get white. only a softer shade of yellowish

No one best way: There are many methods and many whitening agents. See a dentist to discuss the options with you and what would be best in your particular circumstances. Personally, i prefer the take home custom trays with whitening gel. It's a great value and you can reuse the trays in the future. Every case is different. Your dentist can customize treatment for you. Get a consult.

See your Dentist: By accurately brushing and flossing, you will reduce surface stain build up, thereby, keeping your teeth their original color. You need to see a dentist if you want to improve your original color to a much whiter color with a variety of type of professional teeth whitening services. Often younger adults obtain great results with crest whitestrips (professional strength) if not very dark teeth.

See a dentist: Visit your dentist and discuss the option of professional grade teeth bleaching. You can have the option of in office bleaching of your teeth or using bleaching trays for the teeth which can be used daily for your convenience.