While missed calls aren’t ideal, you can let your caller know you’re still there for them by having a great voicemail greeting. The best business voicemail greetings let your customers (and potential customers) know why you’re not available and how they can best get in contact with your business. They are also short and to the point. You usually want to keep your greeting between 6 and 24 seconds long so callers don’t hang up halfway through.
6. You have reached [your business]. All of our representatives are currently busy, but if you leave us a detailed message with your name and number we will return your call in the next two hours. Thank you for calling and have a great day.

Most carriers offer voicemail for free. However, some carriers may limit the number of voicemail messages you can have stored. But this shouldn’t be a problem because not many callers leave voicemails anymore.
Using your cell phone to record a voicemail message isn't always easy. Between remembering what to say and getting the right timing, it's tricky. But your phone does have a playback option, and it's easy to listen to and review your message. For some people, though, cutting off the end of a message is a funny way to trick people and catch them off guard. In most situations, callers won't know it's intentional and will think you're far less than tech savvy. Definitely not an impression I'd want to make.