Keep it Brief. Time is money in business, so if your voicemail is long, chances are the caller will simply disengage before the cue to leave a message even sounds. Keep your voicemail short. The most should be around 30 seconds, and even that’s pressing it. We’ve grown into a country where our attention span can last only about 10 seconds in some cases, so keep it short, brief and to the point. Persuade and Engage the Caller. If someone calls your business, they already have an intention. It’s the quality of your voicemail that plays a factor if they consider you a company they’d like to deal with. This is your chance to motivate someone to engage in a meaningful conversation with you. If your voicemail is shoddy, chances are they’ll hang up, or lose motivation to continue the call. In other words, your voice mail must engage and entice someone to the point that they care enough to leave you a message.
There is no definitive answer here, but you should include one of the two at the beginning of your message based on what makes the most sense.

Once you have your message, you need to actually record it. The exact process varies depending on whether you’re using a cell phone or office phone, but here’s the basic process: Press the voicemail button, or press and hold 1 on most cell phones. Enter your password. Record your message. Listen to the message you just recorded. Follow the prompts to save your message. Following Up on Voicemail Messages
5. Wait for the prompt that begins "Since this is the first time you're accessing your mailbox account" The system will prompt you to press 1 to record your name. Simply state your name when prompted and press # (pound) -- don't include any other message at this point. The system will prompt you to press 1 to record your personal greeting. Callers will hear this recording when you don't answer. Record your greeting when prompted and press # (pound). Your pass code must be a minimum of six digits and can not contain common or repeating sequences of numbers. Choose a number you won't forget. Callers will hear this recording when you are on the phone. For example, "This is Dan Jones. I'm currently on the line. Please leave your name, number, and a detailed message, and I'll return your call as soon as possible. To speak to someone immediately, press zero now." From the main menu, press 9, 1, 3. The system will prompt you to press 1 to record your busy greeting. Record your greeting when prompted and press # (pound). Press the message button or dial 3-9999. When prompted, enter your six-digit Voice Mail PIN and press #. Accessing Voicemail from off Campus Dial 617-353-9999 to call Voicemail or dial your own telephone number to reach your personal voicemail box. Hit * Enter your campus 5-digit extension followed by #. When prompted, enter your six-digit Voice Mail PIN and press #.