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.
I bet you’re not anything close to a “babbling idiot” when leaving a voicemail, but I understand, and until I put the following practices into everyday use, I too felt like I wasn’t showcasing my best self when leaving messages.

Additionally, you will want to close out your voicemail by (re)stating your contact information and name and purpose of your call. This is another little trick of leaving voicemails - people tend to remember the first and last things you say more so than the middle, so by summarizing the important pieces of your message at the end, what you said is more likely to stick.
To change your voicemail message on iPhone: 1. On your home screen, tap Phone. Tap the Phone icon on your home screen to launch your device’s phone calling app. 2. At the bottom, tap Voicemail on the menu bar. You will see a menu bar appear at the bottom of your screen. Tap Voicemail in the bottom right corner. 3. Tap Greeting in the top left