Teeth Whitening Techniques

Ok i would like to make my teeth whiter i have heard many ways but i want to hear real methods that were tried out personally by YOU and worked!!I am also unable to use some US based products since I’m not there( so please don’t suggest things of that type,because I am not capable of purchasing them)
I also used to wear braces and heard that teeth should be whitened after they are taken off(well i didn’t do that)…yet i have also heard that the whitening chemicals aren’t all that safe because for example they cause tooth decay( i don’t know this for a fact).Basically if possible I would like to receive a good(maybe even professional)advice on professionally Whitening Teeth does it have any side affects?(yes i went to a dentist and asked and was told that the procedure is all safe etc)but am still not all that convinced on the whole issue.
I am waiting for answers!
Thank You!