A few suggestions:

• Don’t edit–this is a first-draft mad dash.
• Remember your story is essentially a problem that needs solving. Not your problem, the protagonist’s problem.
• Keep asking yourself ‘what’s the worst thing that can happen next?’
• Remember you’re sending your protagonist into new emotional and physical territory.
• Start at least one subplot. This subplot should also complicate the protagonist’s goals.
• Know your protagonist’s main emotional wound, sometimes called baggage in real life. How is it going to affect his or her ability to solve the story problem?
• Allow the overall atmosphere and mood to creep into the story world.
• Carry a writer’s notebook everywhere you go. You never know when a brilliant solution is going to appear.