Sue Heap appears as eccentric as one of the characters in her award-winning children's books. She sweeps in for her interview wearing a striking array of bright woollen clothes and a bizarre, tasselled scarf, writes Katherine MacAlister.

On further questioning she reveals her penchant for fast, antique motorbikes and travelling to exotic locations around the world with friends, and her unconventionality becomes more marked.

But ask her about her books and her scattiness disappears. She has found her niche, loves it and is doing extraordinarily well for a relative newcomer in such a highly competitive market.

Her first book, Cowboy Babe, won the prestigious Smarties Gold Award in 1998, where children choose a winner from the three finalists.

"At the ceremony, a little boy got up and talked about why he liked the book. He said it was funny and made him laugh which is how a good book should make you feel, and that was wonderful," she says.

You would expect Sue to have hordes of children running around her house creating chaos, but the 48-year-old, from Chipping Norton, has no children.

Yet she obviously empathises very closely with little ones, homing in on the factors and tricks that make reading fun and hold the imagination.

"I have many friends with children, so I've spent a lot of time with them. They have been a great source of inspiration and have given me some great ideas.

"On one occasion I was reading a brother and sister a story and the little girl insisted on bringing her own chair over. Her brother then got very upset because he wanted to sit on the same chair and a huge fight ensued.

"It made me think about possessiveness and gave me the idea for my latest book which is still on the drawing board," she says.

"I am in awe of children and respect them immensely. They are so underrated because of their wonderful imaginations and the way they see the world.

"But it's very important to make the text readable out loud and not too wordy or complicated."

Sue is also a bit of a Peter Pan character, which is perhaps why she has such great insight into children's worlds. I ask her to describe herself and she read a Margaret Atwood quote that sum her up perfectly: "Everyone else is an adult, whereas I am merely in disguise".

Even so, it's a strange trade for a publisher to choose at the age of 36. Sue says she felt like 'a tiger in a cage' as a book designer and mentioned to her boss that she would like to try her hand at illustrating.

To her surprise, her employers let her reduce her contract to just three days a week to see whether she could make it on her own, which, of course, she did.

She started illustrating other people's words, but found it frustrating waiting for a good text to come her way. So she began coming up with her own ideas and stories. These have proved so popular that she is now admired as both a writer and an illustrator in the children's book market.

The illustrations flow freely - landscapes in particular inspire her. On a trip to Arizona, Sue was struck by the desert and mountains and used the colours to create the acrylic cowboy landscape that made her name.

But, she says, she is not a natural writer and struggles with the words that accompany her vivid, bright illustrations.

"One day, I was getting rather late with a deadline for a new idea and I got on the bus in London and thought 'right, if I don't have an idea by the time I get to Oxford I will have to go all they way back to London until I do', and it worked," she laughs.

In between working from home she tours the country reading extracts from her books and attending book signings to alleviate the 'cabin fever' of beavering away all the time.

"I do feel that my job is a huge honour and it still delights and surprises me to find myself in this profession. So many people are in jobs that they find monotonous and demoralising so I think I'm very lucky," she quips as she throws her scarf round her neck and rushes off to Bath, where she is meeting fans at the literary festival.

No doubt they too will be as charmed by her character as they are by Cowboy Babe and his friends.

*Sue Heap is appearing at the Oxford Literary Festival on Sunday, April 1, at Le Petit Blanc, Walton Street at 4pm, where she will be reading her stories during a special children's tea.