Error avoidance

• Design the user interface in such a way that the user can easily build a correct mental model of how the system works
    Use good metaphors
    Use good affordances
  
• Provide lots of advance information
  
• Be flexible with the input format
  
• Dangerous options should not be the default  
• Keep dangerous items/icons away from frequently used commands.
• Warn users if actions have irreversible effects, and request reconfirmation (which should not be the default option).