Reiterate the main point of your message and repeat your name and phone number. This will help the receiver remember your name and message and spares him from having to listen from the beginning to write down your contact information.
One quick way to sound more relaxed is to speak slower – slower than feels natural to you, even. If you rush the sales voicemail, it’ll sound like you’re trying to squeeze in your 50 calls for the day, and nobody wants to feel like they’re just another name on your list. Also, speaking slowly saves you from mumbling – if the contact can’t understand what you’re saying, what’s the point of learning how to leave a voicemail?

Enable the message waiting indicator for your desk phone by checking the box next to Use phone message waiting indicator. 6 Enable Voicemail Notifications 5
When you leave a voicemail message, be sure to identify yourself right away. Give your return phone number at the beginning of your message so that other people don't have to listen to you twice. Speak slowly and clearly. It helps to pretend to be writing your number in the air, which will slow you down and help with clarity. Say when you can be reached.