I wrote my first “long” story when I was 16. Lots of kids wrote stories at lunchtimes and I joined them, but I never really did more than ten pages of scribbles. When I was 16 I had an idea for a story and I ended up writing 200 pages. It was called “Testimony of Fate” and it was about a boy who was born to a drug-addicted mother. It was me putting big words together and thinking “this sounds great”, but I left it in a cupboard for six or seven years.

After that I wrote a play and I did freelance journalism while I was teaching, but didn’t try another novel. Then I went to Poland to teach for six months and I thought this was a good opportunity to give myself a target to write a novel. I remembered I had this idea in my cupboard so I took it with me.

I started looking at it and thought there were a lot of big words there. I hadn’t wanted to include any dialogue, and that just looked weird. But I liked the story and I wanted to do something with it and build on this character that first of all you dislike but learn to empathise with.

By the time I left Poland I had finished the first draft and started sending it out to publishing agents. It was rejected by a lot of places. I started showing people and I got some feedback that it wasn’t commercial, so I redrafted it and sent it out again.

Eventually I got a positive response from a big agent who asked me to make some changes. He said I should make it darker and more shocking. I did that and sent it back, but he had left the company. The only person who supported it had disappeared off the face of the earth. Now I was told that it was way too dark. I got really disheartened and I didn’t touch it for a year.

I left teaching for a short time to work on a magazine where I had this amazing editor who taught me how to make everything crisper and cut out everything that wasn’t needed. After three or four months of that I thought I knew how to make the book sharper, so I edited it and removed all the massively shocking parts.

The plot was still pretty much the same as the one I wrote when I was 16. I removed one main strand and took out the main character’s best friend so I could make him a loner, but the ending was the same and the twist at the end was the same.

Then I went back to teaching and I became a head of English at a school in Hemel Hempstead. We run a very successful programme of author visits - we have had about 20 authors in, including Frederick Forsyth and Jodi Picoult - and I got some good advice from some of them.

By this time it was about four years since I had first gone back to my book. I sent a sample to a fairly young publisher and I was very lucky: they saw it and liked it and asked for the whole thing.

I had learnt not to read too much into anything positive. There is a big jump from asking to see more to saying yes. It had been such a long process and there was so much rejection along the way that I didn’t have much hope left. I didn’t really want to think about it.

It was back in the place where it all started when I heard the news. I was on holiday in Poland and I got a message saying they would like to publish. I was just so happy. All I wanted was to have a copy of it on my shelves, and it was just a thrill knowing that it would go from something on my computer to something solid in print.

It only took about three months before it appeared in print. It was so satisfying. Now I had no gap on my shelf. I love the look of books and to see one that has got your name on it is so rewarding. I have already written my second book. It’s very different. It’s my attempt to write more of a commercial crime tale. I haven’t decided what to do with it yet.

‘Full of Sin’ by Karl Vadaszffy is published by Wild Wolf. www.wildwolfpublishing.com.

As told to Nick Morrison.

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