Click here for details of The Wind in the Willows illustration competition

THEY SAID THAT YOU CAN'T judge a book by its cover - well, I was always a trusting sort and I believed them. I used to think the illustrator's job was just to make the insides and then leave the cover to the experts. But when I started to make my own books I realised that the illustrator doesn't necessarily have to do just the pictures - you can do it all - write the words, design the pages, orchestrate the whole performance.

I began to realise that the cover is the first part of telling the story. And its job is also to look so thrilling that no one can resist picking the book up, having a look inside, and wanting to take it home with them.

It's 100 years since Kenneth Grahame's The Wind in the Willows was first published, and until I found out about this competition, it was at least 30 years since I last read it.

On opening my old copy I was distracted for some time by noticing that I had received it as first prize in a flower arrangement competition around 1973. I wondered what my prizewinning arrangement might have been like - I don't remember being keen on flower arranging as a child. Maybe I just liked entering competitions. Anyway I got my prize, but it was a while before I read it, as I was daunted by the dense-looking pages and scarcity of pictures.

Rereading it now, I instantly rediscover the old familiar elements. I think about how there's nothing I'd be so excited to see as a water rat rowing a tiny boat down the Thames. And I want to draw a map of the places in the book - the River Bank, Toad Hall, the Wild Wood, the Wide World. These places are going to shape the story.

I completely agree with the Rat who says “There is nothing...so worth doing as simply messing around in boats”. One of my favourite things has been falling out of and jumping off boats. There's an element of danger in messing about on the river - as Mole finds out - but the open-ended messing about is where the river sense comes from, and Rat makes it look easy.

The main theme of The Wind in the Willows is about being a good friend, and you feel affection for the characters: the easy-going, capable Rat, Mole, who has to learn how much is involved in making things look easy, plain-speaking Badger, and Toad - a brilliant creation; a high-speed amphibian obsessed with the automobile. He is unsquashable, impetuous, possessed by an almost consumerist passion for the Motor Car (“Poop-poop!”). Toad is enraptured and enthralled by the Car: “The only way to travel - here today, in next week tomorrow!”

So The Wind in the Willows shows this new force for a changing pace of life. And it's torn between the urge to roam in dangerous places and being safely cuddled up at home with toasted teacakes.

A book's cover establishes its identity - it is a pick-up-able 3-D object, and the most low-tech entertainment of all, one that requires no power to make it work except imagination and a little bit of concentration.

I have always found covers a bit daunting to design - but here are some things I do to help to get something together:

- First, don't worry about what a book cover “ought” to look like.

- Read the story and scribble down all the images that you think of.

- Collect ideas to choose from. Look at pictures in books and magazines. Ask “what if?”, “what about?” Try unlikely combinations.

- Do lots of quick little sketches.

- You don't have to draw everything - you can use collage; scraps of interesting papers and materials.

- Remember, the empty space is something that you can use, and simple is often most effective.

There are so many visual elements and dramatic moments in The Wind in the Willows - boats, riverbanks, car chases, wild woods, underground homes, railway pursuits, the battle of Toad Hall, picnics, escaping from prison wearing women's clothing. Where is the “heart” of the book?

I think book covers are utterly exciting. I have bought books purely for their covers. There is a real thrill to seeing your own cover in shops.

So you can judge a book by its cover. And remember, never let a frog drive your car.

Click here for details of The Wind in the Willows illustration competition

For more tips see www.vintage-classics.info/windinthewillows

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