Stephenie Meyer, author of the Twilight vampire romance novels, famously wrote her books after the entire plot came to her in a dream. But not many writers are as lucky as that. There are plenty who start off with a snippet of conversation, or an odd character trait, and who build their stories from there. If you think that all you have to do is sit down and start tapping away, don’t be too disappointed if you find you are having a hard time writing anything.
The best way to get started is not to think that you have to come up with the Great English Novel. Lower your sights a bit. If you plan to run the marathon, you don’t start by running a marathon. You train. It’s the same with writing. Get into training. Do a little bit at a time. But do it regularly, and you’ll be amazed at what you can achieve.
So. There you are. Blank screen. What do you do? The first thing is to ignite your imagination. The best stories are driven by the characters. It’s no good thinking of a plot and then shoehorning characters into it. It never works, because there’s always a point when you think, ‘but X wouldn’t do that…’ What you have to do, is start with characters.
You can build characters by thinking of their possessions; make a list of 10 things you might find in a junk shop, 10 things that could fit in your pocket and 10 extremely expensive things. Now pick three things from each list. These belong to your character. Start thinking about whether they are male or female, what their job is and where they live. How old are they? Do they have any secrets? What do they look like?
And, hey, you have a character.