When you look at the place a scene needs to go and go blank, suspect this. I don’t mean a weary turning away from boredom: I mean where part of your brain is admitting “I don’t know how to do this. I want the scene to do these things, but I don’t know how to make it happen.”
Everything has a learning curve. Just because you can mix colours doesn’t mean you can paint a real likeness in a portrait or make a landscape not only convincing but dramatic. Equally, just because you can write sentences and paragraphs and have a good vocabulary doesn’t mean you know how to make a scene work dramatically or make a dialog zing.
Alas, the only way to learn to write a scene is to write it. If you don’t like what you get, keep the parts that work (not necessarily the cleverest bits) and rewrite it. Over and over. Trying again in a new way is what all creative artists do to get it right, to approach closer to their vision for the work.
It may be you have bitten off more than you can chew. Read the rest of this entry