I think of a first line and take it from there and nine times out of ten it works. A theme emerges a couple of paragraphs in, and I start to get excited as I know at that point I'm going to have a (hopefully) decent story.
I've started applying the same principle to novel number 3, as I'd got a bit blocked and kept going over the same chapters, editing, honing, tweaking, primping (and occasionally going off to make cakes) instead of actually making any progress.
As November is National Novel Writing Month I thought I'd take the opportunity to get the final 40,000 words of the first draft finished, and so far it's working a treat. I don't always know when I sit down to write how the chapter is going to pan out, but somehow it always does, and the more I write the more the ideas come flooding in, and the more I can see how it's all going to be tied up at the end.
I'm not sure this 'flying by the seat of your pants' style of writing is advisable for everyone, but while it's working I'm going to carry on and hope I don't fall down a massive plot-hole at some point and break my ankle.
And look - I've made a blog post!
(Ooh and by the way, my trip to Rome (seems AGES ago now) was fantastic, and I'm so glad I made the effort to get on that plane. I can't say I'd be happy to travel to the other side of the world now, but I know I can cope with a couple of hours in the air. And Italian ice-cream is amaaaaaazing.)