Right. OK. Scrap draft blog. Here we go again. Prince Harry’s announced he’s working on a book about “the experiences, adventures, losses and life lessons that have helped shape him” and ghostwriting’s back on the front pages.

Speculation about Harry’s advance puts it at £15 million to £20 million. A fair chunk of that will probably go to J R Moehringer, the prince’s chosen ghostwriter, whose previous collaborators have included wild child tennis star Andre Agassi (“I hate tennis, hate it with a dark and secret passion – and always have”) and Nike co-founder Phil Knight.

Moehringer is a boyish 56-year-old author and journalist. His own 2005 memoir (presumably written unaided) was called The Tender Bar and is currently being filmed, directed by George Clooney. Clooney, of course, is a friend of Harry and Meghan and it is thought that this is the connection that led to Moehringer getting the princely ghosting job. It’s not what you know, it’s who you know.

The great advantage of finding a ghostwriter by personal recommendation is trust. Moehringer has a reputation for coaxing dramatic bombshell revelations from his authors, especially, it seems, when the matter in question is difficult relationships between fathers and sons. But presumably the rules of engagement have been set and everyone is happy with how things are progressing, though the Prince of Wales may be keeping his royal fingers crossed.

Harry and Moehringer have already been working on the project for a year and a first draft is expected in October, so much of the spadework must already have been done. There may be surprises in store for the rest of us – and for other members of Harry’s extended family – but the Duke of Sussex would not have gone public about the forthcoming book if he didn’t think it was going well.

But how do you find the right ghostwriter for your project if you don’t have George Clooney’s endorsement to guide you?

Even at a less exalted level, nothing beats a word of mouth testimonial from a friend or contact who has worked with a particular writer. If you assume a basic level of experience and competence, which should be easy enough to establish by looking at samples of previous work, there are still a lot of less tangible qualities you will want to ask about.

Is your prospective collaborator responsive, organised, reliable and enthusiastic? World-weary cynicism can get you down over a period of months. Is he or she energetic and optimistic? Many – perhaps most – book projects go through a sticky patch from time to time, and it helps if your ghostwriter can lift you when your spirits are flagging. Was it fun? There’s a lot of hard work needed, from both author and ghost, but a book that’s grim to write will probably be grim to read. Above all, there’s the key question: “Would you choose to work with this ghost again?”

If you can’t get this kind of first-hand recommendation from someone you know, or a friend of a friend, you could always pick a book you’ve enjoyed reading in your broad genre or subject area and try to contact the author, via social media or a note to the publisher.

There is a possible downside to this, as an author who has sweated cobs to write a good book entirely alone, without external help, might feel peeved at your assumption that a ghostwriter was used. To be frank, though, there are not many around these days. Most people who have achieved eminence in a field other than literature or journalism choose to work with ghostwriters to make their books as polished and readable as they can be, just as they use agencies to handle their advertising and accountants to prepare their tax returns.

In the end, though, if you can’t get a personal tip-off and you’ve lost George Clooney’s number, there is one other way to be sure you are working with a suitably professional and resourceful ghost. You could ask a group of ghostwriters who, among their peers, they would be confident to recommend.

That, effectively, is what you are doing if you get in touch with United Ghostwriters.  We are a small, elite group – currently just 14 of us – who work independently as a loose collective, meeting several times a year and exchanging contacts, opportunities, gossip and ideas. There’s no boss, no structure, no P&L – just a shared faith in each other’s abilities and expertise. If you want to know who’s good at doing this stuff, it’s easy. Just ask the professionals.   

Ian Shircore’s latest book is So Brightly at the Last: Clive James and the Passion for Poetry (RedDoor Press)