Think through what you are going to say before you place the call. When men hear the beep, they often freeze up and forget what they wanted to say. If you want to be the go-to guy at work, then you have to exhibit competence on all levels. Don’t spoil your confident image by hemming and hawing and filling your messages with “uhhhhs,” and “ummmms.” If it’s a really important call, consider writing out what you want to say beforehand. If the person picks up, great, you now have some notes to remember what you wanted to talk about. If they don’t answer, you can leave a clear and concise message.
Avoid piecing your voicemail together on the fly — as I mentioned earlier, a good one is backed by preparation. So prepare, prepare, and prepare some more.

As the odds of receiving a call back from your voicemail message are already low, you need to be very specific about what you say in your voicemail to give you the greatest chance of getting a call back. What you absolutely do NOT want to do is make yourself sound like a salesperson making a cold call. Instead, you want to sound like a very confident business colleague who deserves the respect of getting a call back.
Please note that if you record an unavailable greeting, it will be used instead of the default message with your name recording.