Matthew Bruce Alexander
I have read about lots of ways to deal with writer's block, but the only way I deal with it is to force myself to sit down and write. For this reason, I advocate preparing your story in advance, at least to some extent. There may be times when your artistic flame is sputtering; happens to everybody. But the technical aspect of making enjoyable prose really has little to do with artistry. It's simply about knowing how to fashion it. The brilliant turn of phrase or apt metaphor might have to come in the second draft, when that flame is burning strong, but you can relate a story, even if you have no ideas at the moment, if it is planned or semi-planned out beforehand.
I also often warm up to write by reading something I have written, preferably from the same story I am currently engaged with. Sometimes that is sufficient to remind me that I can do this, I can write good prose and even come up with a creative idea now and then.