I am certain that this process is different with all writers. We all have our ways of working. It is also clear that it is not always the same with me. Sometimes I have carefully plotted out a novel while at other times, I work with a vague idea and allowed it to unfurl as I progress.

I used the Butch Cassidy principle: there are no rules.

But always, as a novel progresses, as a character develops, a novel takes on a life of its own. It is a coalescence of ideas. I will wake up in the middle of the night with an idea and have to get out of bed to write it down or it is likely to go.

All my novels start with an idea. That might be sparked by a news story, a book I am reading, a programme I am watching or a train of thought. One idea is never enough though. It has to be married to others.

Often the end of the novel is what emerges first. I will often write the end first.

Always there comes that time when you sit at a computer (or a typewriter) and begin. You have a blank page in front of you and a head full of ideas. With me, there is excitement and anticipation.

The ideas have to have a setting and characters. With Sci-Fi, there are infinite possibilities.

I often write a beginning that is later superseded by another beginning. Once I get that first sentence down the rest seems to flow. The characters develop, the scenes change, the ideas flow. I struggle to keep up. It becomes like a line of dominoes. One knocks over another which sets two more falling over. I write quickly, trying to keep up with the ideas, following the characters and inventing settings. I work on the principle that with the first rewrite I can expand and fill everything out. It is as if the first draft is a rough sketch that gives the outline of the book. The rewrite starts to fill in the colour.

It is usual for me to increase the word by a good fifty per cent.

The second rewrite will again add a lot more.

The third rewrite is more of an editing process – changing words, altering sentence structure, correcting grammar.

The most important part for me in writing a novel is to get that first sentence down. After that, it is like an egg-timer. The sand grains are the ideas, characters and settings; I just allow them to trickle through until my head is empty.