Consider for a moment how your phone is currently being answered. Professional courtesy is quite often not the standard for many college students. An abrupt "Yeah!" could be listed among the more courteous greetings. The more outrageous remarks will often buy you a major black mark in the professionalism category—even if it was your roommate answering your phone and acting crazy. A simple "This is ____" is always a pleasant change for a college student call. Make the change today, before the next (or first) employer phone call. If you have a landline, you should also encourage your roommate to do the same.
Recording your professional voicemail greeting can sometimes cause apprehension, especially if you have never done so before. You may find it helpful to go to a very private location when you are ready to record, and this can help ensure there is no background noise when you are finished. Take a few minutes to review the list you made earlier, and rehearse the greeting a few times if you are extremely nervous. While you are rehearsing, make sure your speech flows smoothly and you do not use filler words like "uh" or "um". Is Amazon actually giving you the best price? This little known plugin reveals the answer. Professional voicemail greetings should be pleasant in tone to encourage customers to call back later.

Solution: Voicemail should be a part of your company’s overall phone system, Baldwin says, so you can maximize functionality and integrate it with other tools and business applications. “If your voicemail is separate because it’s stored solely on your mobile phone, you need to get it off that and put it on the messaging app that comes with your business voice phone service,” he says.
You have stated your calls-to-action. Now you have to make sure they know the process to follow. If you want your customers to leave their voicemail messages, you have to tell them from the start, “Kindly leave your name, purpose of your call, and how to contact you.”