Look at what you write. Don't settle for dull words unless they suit the mood. Take a good sentence and make it better. Paint it. Sculpt it. Add warmth and colour.
Enrich your language with the magical vocabulary you have at your disposal. I don't mean use three or four adjectives in a row. I don't mean pepper every sentence with superfluous adverbs.
I mean that you should lavish your work with the best words you know, carefully chosen for their beauty and fit.
Just like the perfect dress.