At the least, the recording should include your name, the name of your company and your office hours. You can also include the best way to reach you—such as an email—and provide that contact information. If they can leave a message, let them know in the message.
The above section details types of phrasing to avoid; however, it doesn’t detail what users should NOT say on their greeting. Though this is a bit loaded, as there are hundreds of combinations of things one shouldn’t say, there are some key components users should ALWAYS avoid. a. Forget About Slang: You should strive to be as professional and welcoming as possible in your greeting. While this may steer you towards using slang, in an attempt to make callers comfortable, it’ll most likely work against you. As a professional, your demeanor, tone, and speech should be clear cut and well articulated. Using slang undercuts this and works against you. b. Don’t Even Think About Profanity: This is a no-brainer. Never, under any circumstances, curse in your greeting EVER! c. Keep Your Sentences Clean, Don’t Ramble: Introduce yourself and give your caller specific direction. Avoid long diatribes detailing tangent thoughts. Keep it simple and quick. d. Always Return Your Calls: It’s important for callers to feel they are valued. Nothing dissolves this quicker than a greeting that doesn’t stress this. For example, “I’ll call you when I can,” “If I don’t return your call, please call back”—these phrases are terrible and completely destroy any good will you may have with a caller.

“Keep your voicemail messages short, sweet, and snappy," advises Will Craig, Managing Director of LeaseFetcher. "Don’t try and go into the nitty gritty details of the discussion you’d like to have with them—save that for your actual chat. Alternatively, don’t leave them in the dark about what you want to talk about either. A simple 20-second voicemail letting them know the nature of your query will suffice."
A word of warning: These greetings will not do you any favors if you're in the midst of a job hunt or work in a conservative industry. Always remember your target personas. If there's a chance they won't appreciate your sense of humor, opt for a straightforward greeting instead.