I am, of course, a frustrated rock star - I'd much rather be a rock star than a writer. Or own a record shop. Still, it's not a bad life, is it? You just sit at a computer and make stuff up.

I'm interested in Scotland now and then, how it's changed. I want to get the reader to think about that by thinking about something from the past. How has society changed, how has policing changed, have we changed philosophically, psychologically, culturally, spiritually?

I still think most writers are just kids who refuse to grow up. We're still playing imaginary games, with our imaginary friends.

I think writers have to be proactive: they've got to use new technology and social media. Yes, it's hard to get noticed by traditional publishers, but there's a great deal of opportunity out there if you've got the right story.

I've always written. At the age of six or seven, I would get sheets of A4 paper and fold them in half, cut the edges to make a little eight-page booklet, break it up into squares and put in little stick men with little speech bubbles, and I'd have a spy story, a space story and a football story.

I love short stories - reading and writing them. The best short stories distill all the potency of a novel into a small but heady draught. They are perfect reading material for the bus or train or for a lunchtime break. Everything extraneous has been strained off by the author. The best short stories pack the heft of any novel, yet resonate like poetry.

I'm often asked how I write books, but I don't think my approach is suitable for everyone. If I walked into a creative writing class, all I could say to them was 'I tend to make it up as I go along.' I'm not sure that's brilliant advice.