The reason you're writing a story in the first place is, I hope, that you have something to say. Something new, something that comes from your heart, from your imagination. Even if you're retelling an old tale—and the retelling of old tales is a noble tradition—you still want to give it your own voice, your own sensibility. So you need to start by being clear about what it is you want to say. You might not know the whole story at first (often you don't!), but you should have something in your belly that says, This is my story, and I need to tell it!

At the same time, think carefully about whether the story really is yours. Is it new, different? Or is it derivative, tired, and clichéd? (Let's face it—not too many people want to read your version of last week's Stargate, at least not if you're presenting it as a new and original story.)

Originality

Chances are, you're bubbling over with ideas already or you wouldn't have gotten this far. Take those ideas and examine them. Turn them over in your mind like stones you find on the beach. Search them to find the glint of gold, or the sparkle of the crystal gem inside. Don't be satisfied just retelling an old story; search for unexpected elements within your idea.

Search for the things that will give it conflict, and tension, and plot.