Step 4; Test the prototype, in he environment or product it will be used. Make a point of getting feedback from real people before you commit to production, when the prototypes get more detailed and closer to a final product, however, you might want to consider testing on a wider range of users so as to get the most relevant and helpful feedback.
Step 5; Let the Users and customers contribute Ideas, consider testing out several versions of your prototype on users to gather feedback. This helps to solicit critical feedback — because people tend to hold back on overtly criticising prototypes. When you present your users with alternatives, you allow them to compare the various prototypes and tell you what they liked and disliked about each version, and so you will get feedback that is more honest.
Step 6; Revise and adjust the prototype, and repeat until