In order to bring believability to one’s voice the voice actor must have a flexible voice. Therefore you must train your voice so that it can embody all the vocal nuances of a variety of characters. For starters you must give up unhealthy habits like smoking and excessive drinking as these have a significant effect on the performance of your vocal chords. Smoking can affect your capability to moderate breath control. Do breathing exercises by lying flat on your back and inhaling deeply and slowly; then breathe out slowly. The next step is to practice diction regularly. You can work with a voice coach or practice along with tapes so that you can be sure that your pronunciation is clear and precise.
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