With 17 novels, a James Bond reboot, short stories and multiple screenplays under his writerly belt, is it an odd question to ask why William Boyd writes? He answers quickly and wryly: “It is a good question and a hard one. Basically, I can’t imagine doing anything else.”

Boyd avoided a family tradition of going into “sensible” professions. At a Guardian Live event for his latest book Sweet Caress he spoke to critic Alex Clark about his career, peppering his reflections with advice for would-be writers.

While being a successful novelist “is not something you can buy or learn,” he said, and comes from “a combination of a gift and application, talent and luck” there are four questions you need to ask yourself before you set out on a career as a writer.

1. Can you write?

So far, so obvious. “You have to be able to write well,” Boyd said. “Not stylishly. You have to be able to express your thoughts in a manner other people can understand. You could write simply – something like James Joyce’s Dubliners, with a very limpid prose – or you could write a Finnegan’s Wake. But you have to be able to write: if you can’t, stop.”

Boyd writes his first draft with pen on paper – something that’s rare among his contemporaries. “There is something sad about that; the scratchings out and deletions mirror the thought process of a novelist, whereas a book on screen is perfect. Cadence, rhythm and sentence length, shape, style. If you are on line six you know your sentence is out of control.”

If you are on line six you know your sentence is out of control William Boyd

2. Can you plan?

How does one plot a whole life full of seemingly random moments? Organisation is key. “When you’re constructing a life you have to use a lot of artifice to make it seem artless, a lot of organisation to make it seem random – because life is random,” said Boyd. “It’s part of the construction, the technique of writing these long novels that cover many decades: you have to encompass that random chance element that exists in everybody’s life. I don’t write chronologically, as I’d end up writing a 5,000-page novel.”

While writing one book, Boyd always has two or three ideas brewing. “Books never arrive fully formed,” he said. “I get maybe six or seven ideas a year that I think could become novels. I let them stew and brew. Some I never expand on, but these ideas never start fully formed. I don’t believe that romantic notion that a character can take over and tell you what to do; just have an idea and see where it leads you.”

With all the planning in the world, Boyd still feels surprise at what flows from his pen. After writing the death scene of his hero, Logan, in Any Human Heart, Boyd felt real sadness. “I remember coming down to the kitchen and saying to my wife: ‘Logan has gone’ – as if a friend of ours had passed away,” he said, to laughter. “But I had planned it, envisaged it.” He then had “an enormous drink” to mark the passing.

3. Do you have a great imagination?

Boyd believes this attribute is a gift that cannot be learnt. “You either have that or you don’t,” he said. “Now, most people can imagine what it is like to be burnt alive, for example, but do you have an imagination that works in subtle ways?” If you can imagine the mundane and take pleasure in everyday life, you may be suited to novel writing, he says. “You should think: ‘Eight-hour delay in an airport? Fantastic!’ I can have three stories out of that. If you don’t take pleasure out of that texture and detail in your every day life, you can’t write novels.”

“I have never killed anyone, you’ll be glad to know, but I have in my novels,” Boyd said. “You have to be able to imagine situations you will never experience. Part of the process of writing is to imagine it and put it on the page, whether that is killing someone, being told you are sterile, or having sex with an obnoxious French journalist. You have to imagine what it is like and somehow make it real.”

4. Do you have the stamina?

“There are rare examples of authors nailing it on novel one, but a whole creative career is a long haul. It takes so long to write a novel, so if you don’t have the stamina, don’t do it,” Boyd said. “I know a lot of poets who think about becoming novelists, but then say: ‘But I can write a poem in an afternoon.’ You can’t do that with novels.”

I will never abandon a novel because I make all of my mistakes before I write one word William Boyd

For Boyd, the whole process takes about three years – two years of which are taken up researching, reading and planning, filling notebooks and building a structure. While doing this, Boyd holds a Q&A with himself to clarify issues of character or plot.

“In Sweet Caress, my main character is a woman photographer: that is my starting point. But the whole book is a 100,000 questions: what is her name, how tall is she, what colour are her eyes? And all of the questions begin to shape how she deals with people, situations and what makes up her life.” This process takes twice as long as it takes him to write and he only begins to write once he knows the end.

“My method won’t be for everyone - some people like to just start writing. But I will never abandon a novel because I make all of my mistakes before I write one word. I discard my useless subplots and characters before I start - whereas some people spend 18 months on a novel only to abandon it. I spend two years thoroughly thinking it out and nine months to a year writing. But I write with confidence – I never wonder what will happen next. Iris Murdoch said there is a period of invention and a period of composition - I have borrowed that for myself.”

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