1. Do Not Edit
To many of us, myself included, are tempted to go back and edit words and sentences as we are writing out the first draft of a story. This is a huge mistake because it breaks up the flow of our writing and it cuts back on the writing we do get done. A first draft is just that: a first draft. Don't worry about misspellings or sentence structure. Just concentrate on getting the story out and onto the screen. Edits come later.
2. Don't Take Time Off
When you begin your first draft, plan on working on it every single day. Taking a day off from writing can lead to taking a few days off and then a few weeks off. By the time you get back to your story, you will have lost your initial enthusiasm for it and all that hard work at the beginning will have been a waste of time.
3. Don't Worry What Other People Will Think
The biggest story killer is worrying about what other people will think of your story. Don't even think about other people. Don't write to appease your mother and don't cut out scenes because the neighbors will be offended. Write from the soul. And if you are truly worried about what other people might think, publish under a pen name.
4. Don't Write Without a General Direction
Whether you outline plots or not, you still need to know what your story is about. This can be a broad statement, such as, "This story is about a woman who fell in love with the wrong type of man." I you do outlines, create a map of the story so you know where you are heading. Know your ending. Is your character going to resign herself to a life of misery or will she strike out on her own? You don't need the finer details to begin writing a first draft, but you do need to know the general direction of your story.
5. Don't Complicate the Plot
We've all read those stories with complicated, intertwining plots. You may even want to write a book that has numerous twists and turns. That's great! But don't attempt to do it all on the first draft. You're first draft is for getting the story down. After the story has been written, you can begin to add more depth and plot twists to the mainframe of your story in the 2nd and 3rd draft. Build your story up. Don't expect it to be all there in your first draft.