Kind of a random thing, but thought I'd suggest some writing exercises. These can help unstick you, if you're in a tight spot, or you can just do them if you're bored:
1.) Describe a scene in as much detail as possible...From a blind person's perspective. Ergo, you can describe everything EXCEPT what they can see.
2.) Think about your favourite food. Now write a passage about it to make it sound like the most disgusting thing ever.
3.) Write a happy story about a pokemon you don't like.