First you need to know how much time your phone system or provider allows for the duration of the greeting. Some are 30 sec some are longer. Then you need to have a few ideas of what you want to say, or ask your callers.
How do I change my voicemail greeting on Android? Open the Phone app . Press and hold “1” to call your voicemail. Enter your PIN and press “#”. Press “*” for the menu. Press “4” to change settings. Press “1” to change your greeting. Follow the recorded instructions. Access your main voicemail menu. Listen for instructions to enter your password. From the main menu press 3 for Personal Options. Press 2 for Greetings. Press 1 to Change Greeting. Press 1 to Record personal greeting or press 2 to select the standard greeting. Tap on Call settings and select Voicemail. Tap on Voicemail service and select My carrier or My operator. Tap on Setup, select Voicemail number and type in your voicemail number. Tap on OK in the Voicemail number changed popup.

Microsoft continues to ride roughshod over people who have been users - at not inconsiderable expense - for YEARS. Skype itself is NOT free to use (even leaving aside my paid phone number) because it wastes hours and causes anxiety and frustration, each of which has a cost. Skype was never perfect but it had some degree of honesty before it was swallowed up by Microsoft.
Funny Voicemail Greetings. Composing these types of greetings are fun, but they aren’t applicable for some situations. You may make a funny voicemail greeting for your own personal voicemail box. However, it’s not appropriate for professional or business phones. Here are some humorous examples for you: You have reached [mention your name].