The most professional approach would be to avoid using your personal cellphone, and go for a modern "business phone" solution. Luckily these days the options can be very diverse and inexpensive.
Hi there! You’ve reached [LinkedPhone – Where Freedom Rings!] We’re away at the moment but please leave your name, number, and let us know how we can help you. We’ll make sure the right team gets back to you within [the next 24 hours]. We appreciate your call. Thank you.

I have a confession to make: I haven’t recorded a new voicemail greeting since 2014. In the past four years, I (hopefully) have become more articulate, poised, and self-assured. But hear my voicemail recording, and you’d think I was still new to the work world, a little unsure of myself — and probably not an authority. Obviously I need toupdate it. And if you haven’t changed your voicemail greeting in over a year, you’re likely in the same boat. After all, a professional voicemail recording boosts your credibility, makes you seem more competent, and encourages whoever’s listening to it to continue the relationship. A relatively unprofessional one — like mine, for instance — does the opposite: It encourages prospects, recruiters, and potential connections to run in the other direction. With that in mind, I’ve written 18 unique voicemail greetings for every situation. Pick your favorite, practice a few times, then record your new voicemail.
Your prospects need to hear something which can make them hold on to what you are trying to tell them and that starts with a good attractive statement.