What are Norman Seven Principles for Transforming Difficult Tasks into Simple One

Norman’s execution–evaluation cycle, in which he elaborates the seven stages of action.

• Use both knowledge in the world and knowledge in the head.
• Simplify the structure of tasks.
• Make things visible.
• Get the mappings right.
• Exploit the power of constraints, both natural and artificial.
• Design for error.
• When all else fails, standardize.