Should avoid:
-watching a funny movie while trying to write a serious story, it always backfires (has happened one too many times)
- trying to write a story when you have animals crawling all over your computer, fur and buttons don't mix well (another frequent thing that happens to me)
- never try to write when friends/family/ or husband in my case is in the same room because then they will proceed to read over your shoulder and give pointers (some good and some very bad!) or worst try to write your story for you!