THE PAGE WAS BLANK. Nobody knew what I was trying to do; nobody would have cared. Nobody else could make a mark unless I did. The blank page is terror.

In the top right hand corner, I put “4.03pm, Tuesday, 4-ix-1956.” (Either it would be of significance or it wouldn’t, and I stuck it there in case I needed to remember.) Below that: “Ch. I, 1.” And on the first line, The Weirdstone of Brisingamen.

So it began, and has continued. The blank page is always terror.

A Damascene moment on the road to becoming an Oxford academic had taken me by surprise, and I didn't know how or where to start.

All I had was the dreadful necessity to write. Here is what I wrote: “Colin and Susan Whisterfield, ten-year old twins, sat in the attic window and gloomily watched the rain slide slowly and stickily out of a dull, grey, London sky into the dull, grey, London streets, as it had done every day now for over a week. It was the most boring rain imaginable.”

It was not as boring as the prose. Lesson No 1: “The ability to read literature does not automatically confer the ability to write it.” After the first few pages I drew a line across what I had perpetrated and inscribed the single, accurate word “MUSH”, and began again.

I wrote what I saw in the cinema of the head, without planning or even knowing what was happening or going to happen. Older people, meaning well, urged me to stop. I was being irresponsible. I could write as a hobby, after work and at weekends. I should wait until I retired. I couldn’t tell them. They would not have understood, any more than I did then.

There was a single moment of encouragement. Through serendipity, I found myself in the stall of a urinal next to my old headmaster. He said: “What are you doing, apart from the obvious?” I said what I couldn’t say. “I’m going to write.” He said: “Good. I always hoped that I’d get one.” One. One was enough for him. I began to understand the immensity of dancing on ice floes.

Two years later, the manuscript was finished and illegible with corrections, so I had to spend six weeks making a fair copy in longhand for a typist. It is hard now to imagine the risk of having the unique text, with no backup, nothing but the vulnerable paper. When I collected the bound typescript I waited until I was in the street before I opened it at random. There were the words that I knew only as the ink of my handwriting now formalised as the early shape of a book. I vomited into a privet hedge.

Two years to write the first novel. Two years to find a publisher and to get the book on to the shelves. Four years of casual labouring and the dole.

Much has changed in those 50-years-to-now; but one thing has not. The more critically successful a writer becomes, the more need there is for a strong editor. To think otherwise risks artistic suicide. A trusted editor, dedicated to the text and sensitive to its author, is the making of a writer and is the great teacher. On the high trapeze, the Flyer may be the one who draws the applause from the crowd, but it’s the editorial Catcher who times the flight.

I have been fortunate in my editors. The readers’ reports for the three novels that followed my second all recommended rejection on the same grounds each time: that the new book was different from the previous one. And each time the editor had faith, and published.

By such means I have survived half a century of scribble. The earliest surviving example of my family’s writing is more simple: the attempted signature of William Garner, dated November 14, 1813, for the lease of a cottage and croft with “10 or 12 roods of potatoe land”. It is a cross, made by a pen held as a dagger. More simple, perhaps. For me, it is the most powerful sentence. And at 4.03pm, Monday, 4-ix-2006, I shall enter a second half century of dancing on ice floes, in the fifth year of the ninth novel. The page is blank.

Alan Garner appears at THE TIMES Cheltenham Literature Festival 6-15 October. Call 01242 227979 www.cheltenhamfestivals.com

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