1. The name after long years of birth can not be change so easily by making corrections in the birth certificate.
2. However there is no legal harm if you start using the new name and to avoid any complications you should use an affidavit.
3.in the affidivit you will have to mention about your both names and use of your new name.
4. The affidavit should be executed before the Magistrate and a paper publication is to be given.
5. Once that is done you can start using the new name.