With all the amazing different types our iPhone’s can do, we sometimes forget they are also a phone. While calling people isn’t nearly as common as it once was, it still happens and your phone still needs to be able to make and receive calls. However, there are bound to be times when you are not by your device when a call comes through. But instead of just missing the call entirely (which could be incredibly important), why not set up voicemail on your device. While it might sound like a daunting task, it really isn’t that bad or hard to create. However, if you are confused about how to set up voicemail on your iPhone 6S, worry no more. This article will go into how to set up your voicemail on your device with ease.
Keep callers on the phone with messages on hold. Make announcements while they’re waiting or being transferred.

To set up voicemail on your iPhone, tap Phone on your main screen. Tap Voicemail in the bottom menu. Tap the Set Up Now button. Choose a passcode to secure your voicemail. Use the default greeting or record your own. Finally, tap Save to set your outgoing voicemail message.
On the iPhone, go into voicemail and tap "Greeting". Record a few seconds of something and tap stop. Before you tap save, use iFuntastic or SFTP to navigate to /var/root/Library/Voicemail on your iPhone. You'll see a file called "Greeting. amr". This is the audio you just recorded. Delete that file and replace it with your custom message which should then be renamed to "Greeting.amr". Tap "Play" on the iPhone to verify your message works. If it plays, tap "Save" and your custom message will be uploaded to AT&T's servers.