From the Skype for Business desktop app (if you are running Click-2-Run build C2R 8201.1002 or later), select Set Up Voice Mail. Change your Call Answering Rules You can change what options your callers have when they reach the voicemail service; get disconnected, hear your greeting, record a message, choose to be transferred to the number or user you select. Change your prompt language This is the prompt language that is played to callers. For list of supported languages, see Languages for voicemail greetings and messages from Skype for Business. Configure your Out of Office greeting This is the customized greeting message that is played to callers when your status is Out of Office. This option can be activated "Always," when you have an active "Auto Reply" in Outlook, or whenever you have an out-of-office calendar appointment.  Where you can get your voicemail messages from
Some of the best business phone systems allow you to create multiple voicemail greetings so that you don’t have to constantly re-record your greeting. This is a great feature as it gives you the option to have different voicemail greetings depending on whether a call comes in during or outside of business hours.

2. Hello, you have reached the office of [your name]; I will be out of my office starting on [date] and will be returning on [date]. You can call me when I return or leave a brief message. If this is an emergency I can be reached on my cell, which is [your number].
Keep a pen and paper next to you. Keep track of calls by writing down the person’s name, the time he or she called, and the reason. It’s best to write the information on a phone memo pad with carbon. This keeps the calls organized in one place, and when it isn’t for you, you can give a copy to the intended recipient.