What's the best way to keep teeth from getting stained? I'm having my teeth whitened in two weeks, but once that's done, what would be the best way to keep them white? I don't smoke..

Brush . Brush as soon after you eat as possible. Consider using an at home system for periodic touch-ups after the initial whitening.
Your . Your teeth will color again over time (one year?). That is from normal use. You should have bleach trays to take home. This allows you to do touch ups every several months or so. When you touch up, it will only require one treatment o about 20 minutes (depending on the solution). And they will be very white again. Also, you will notice that those whitening toothpastes will work very well to help keep your teeth their whitest. In my office, I use the zoom system and include a set of trays and solution with the in-office whitening treatment - because touch up is important over time.