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How to develop a friendly tone of voice
Breathe from your diaphragm to control your voice.
Making your tone of voice friendlier requires you to be aware of how fast you talk and how high and low your voice gets. Use strong breaths from your abdomen for better control.
To check if you're breathing from your diaphragm (the muscle that sits right below your lungs), watch yourself in the mirror while you breathe in. If your shoulders and chest rise, you're taking shallow breaths without using your diaphragm.