Apr 27, 2013 · If the caller needs to a have longer conversation, then they should schedule a meeting or a coffee and have the conversation face to face. Or plan a conference call. Let the phone ring at least 6 times (or until the jump to voicemail occurs). This gives the receiver time to put down what they are doing and come to the phone.
All that being said, as voicemail is still thing, and carriers do offer it with every account, iPhones support voicemail. Here’s what you need to know if you want to set it up.

Once you have your message, you need to actually record it. The exact process varies depending on whether you’re using a cell phone or office phone, but here’s the basic process: Press the voicemail button, or press and hold 1 on most cell phones. Enter your password. Record your message. Listen to the message you just recorded. Follow the prompts to save your message. Following Up on Voicemail Messages
A relatively unprofessional one — like mine, for instance — does the opposite: It encourages prospects, recruiters, and potential connections to run in the other direction.