Determine how long your fight scene will be. These scenes generally last from 5 to 10 minutes. Read the fight dialogue out loud with a timer so you know how long your scene will last.
Give your characters funny but memorable dialogue in the fight scene. This will create an emotional bond with the audience.
Choose a fighting style that you are familiar with. If you are not familiar with a fighting technique, buy or borrow a book with pictures that have descriptions under each photo. Read scripts and watch movies that incorporate the fighting style you want to use.
Stand in front of a mirror with a friend and act out the fight scenes. This will help you determine if the action is realistic or not.
Ask someone who has been in a fight to read your script. Ask him if you need to change or add anything to make it more realistic. Review your script.