Hiya beccaac2901
I'll try and be succinct
1) Wait until you are 21
2) Get it done by a DENTIST (the only person other than registered dental care proffesionals legally allowed to provide diagnosis and treatment of conditions of the mouth and oro-facial region, NOT by anyone else)
3) There is always some sensitivity, this varies from person to person and is reduced whith certain techniques
4) It nearly always works to some degree if a bleaching agent is used
5) VillageVicar is wrong on a number of points, bleaching does not 'damage enamels', it does not 'brittle your teeth' and it most certainly does not 'accelerate decay'
***Bleaching agents are used in dentistry to kill microbes responsible for tooth decay in root canal treatment****