What does the tone of your voice sound like? Does it reflect confidence? Strength? Assurance? Are you prepared sufficiently to be conducting the call? Do you need, perhaps, to call the client back when you are prepared? If you are warm and interested in what they are saying, you will sound warm and interested on the phone. Your speaking on the phone reveals a lot about you to the listener. (Because they can’t SEE you they are more tuned in to your SOUND).
When speaking and thinking about the key points you want to emphasise, make sure the inflection of your voice does just that. Inflection alone can change the meaning of a sentence. Whatever you do, don’t sound uninterested or bored. Your client needs assurance and needs to be confident in what you are saying. Make sure your voice is clear and strong.
Practise, practise, practise. The delivery of your message is really important. Don't be afraid to rehearse the messages that you frequently give. (For example, advice to clients and stakeholders). Or even the frequent messages you convey with phone calls. If the message is sensitive and important, practise it beforehand. How does it sound to you?
What do you sound like? For example, when you record your voicemail message, what do others hear? A smile? Confidence? Authority? Don't be afraid to record your voice as you are practising. When you hear the recording of your voice, you hear exactly as others hear it. And this is, most often, a higher voice sound than you hear yourself.
Similar to tone, but different. The energy in your voice allows people to feel like they are in the room with you and that you are tuned in to what they are saying. One thing to watch is the speed at which you are speaking. You can speak much faster than most people can keep up with. Especially if you are speaking about and using technical phrases – and they are not common to your clients.