An author confided to me recently that, however much we tell ourselves that the Lit Fest is all about culture, it’s equally about sales. Well, certainly a signed book is a sold book.

Hay-on-Wye is a biggie. My first appearance there was damp. As in rain. And, to some extent, squib. I arrived at a sodden country hotel at dead of night having been driven from London after a performance at the Donmar.

The front door would be left unlocked, I had been assured, my room key on a table inside. I tried the door. It didn’t move. Nothing. What to do? The driver splashed up the steps with my overnight bag, lifted the iron knocker and slammed it down.

We listened. Walter de la Mare would have appreciated the dilemma.

Suddenly the door swung outwards, and a tousled Terry Jones (Python and medievalist) stood blinking on the threshold. Courteously, but with voice of steel, he said: “It opens the other way.”

I grabbed my bag, groped past him, located the key and slunk soundlessly to bed.

My “event” next morning took place in a sort of tented sauna. I refrained from any jocular reference to the venue as a “big top”; I had been warned that organisers are sensitive. It’s a marquee.

I read from Acting Strangely. The rain beat down. I told a true story about playing George VI in an American mini-series and my approach to his speech difficulties. I mentioned “Monty” and Churchill. They also had impediments. I did impressions.

The audience shifted uncomfortably. I heard whispers of “non-PC”. Or was that hissing? Oddly, though, when I moved on to Just William and a full-blooded characterisation of Violet Elizabeth (“I’ll thcweam an’ I’ll thcweam ’til I’m thick), they rocked with laughter. Fictional lisps OK at Hay.

Cheltenham Festival and a lesson in salesmanship from John Major. I had slipped in at the back of the Town Hall where he was spell-binding a full house. Before completing an anecdote, he would hesitate, then announce: “If you want to know what happened next — read the book!” Literary cliff-hanging. Afterwards he signed stacks of John Major: The Autobiography.

Festival signing is a competitive craft. I learnt this from a veteran Chester Fest author: first, observe how long your personal queue is. If shorter than, say, Neil Gaiman’s or Robert McCrum’s, avoid losing lit-face by taking your time with each punter, er, reader. Engage in friendly banter and ask: “Who shall I make this out to?” Then add, to your humble signature, “with warmest good wishes . . .”

This literary filibustering ensures that, even if your queue had started off appreciably shorter than Gyles Brandreth’s or, dare I suggest, Martin Amis’s, you’ll still be selling, signing and smiling while greater writers are back in the green room talking about their royalties.

Beware the woodwork people. These are folk who seemingly come out of nowhere and whom you once knew slightly. In my case they have ranged from a Norwood neighbour of my childhood, whose stick insects I tended when she went on holiday, to a normally amiable former teacher of mine who greeted me, at a Croydon mini-Fest, with a humourless, “I think your book should be pulped.” Ooh-er.

Turned out I had written that he’d been “from Cambridge”. He informed me balefully, even as he proffered his copy, “I was at Oxford.”

Never mind; he bought the book.

Martin Jarvis has written two volumes of autobiography: Acting Strangely and Broadway, Jeeves? (both Methuen). He stars in Taking the Flak, the new BBC Two comedy-drama series , starting July 8

Top five festivals

London Literature Festival
Southbank Centre, July 2-16 Buzz Aldrin’s only UK appearance is the jewel in the crown of a lively festival that also features Arundhati Roy, Vikram Seth, Peter Ackroyd and Jeanette Winterson (0871 6632500; www.londonlitfest.com).

Festival at the Edge
Stokes Barn, Much Wenlock, Shropshire, July 17-19 An entertaining and wide-ranging celebration of oral storytelling, with workshops, story rounds and informal music sessions for adults and children (01939 236626; www.festivalattheedge.org).

Port Eliot Festival
St Germans, Cornwall, July 24-26 Pitch your tents in acres of 18th-century landscaped walled gardens and listen to Sarah Waters speaking and Louis de Bernières playing the mandolin (01503 230211; www.porteliot festival.com).

Edinburgh International Book Festival
Charlotte Square Gardens, August 15-31 Edinburgh lives up to its status as the world’s first Unesco City of Literature with this, the world’s biggest literary festival. Highlights will include Margaret Atwood launching her new novel The Year of the Flood, plus Tracy Chevalier and Richard Dawkins (0845 3735888; www.edbookfest.co.uk).

The Times Cheltenham Literature Festival
Cheltenham, October 9-18 Ten guest directors (including Monica Ali, Sandi Toksvig, Jonathan Coe and Simon Armitage) take over to mark the festival’s 60th anniversary (0844 57677979; www.cheltenhamfestivals.com).

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