168 Design for Operational Excellence it can be used when new products are introduced into an existing value stream as well as when an existing process is being redesigned. Building full-scale mockups allows the operators to see a life-size representation of the applied tools that are being used to achieve each guideline, such as a one-piece flow cell connecting to a FIFO. With this mockup, operators can figure out exactly where material will be placed, how it will be presented, where tooling will be placed, where the next setup will be stored, and much more. Once the mockup has been created and all the details have been worked out, the equipment can be placed in accordance with the mockup, and production using the new design can begin. It is im- portant that we implement the new design starting from the cus- tomer and then moving upstream to raw material. Our implemen- tation plan should reflect this, and it needs to be followed in that order. Flow could break down quite often if we were to start from the raw material end or in the middle in a specific "targeted area for improvement" without having established a steady flow at the cus- tomer end first. What You Would See on the Shop Floor Once we have educated the workers on the design objectives, the process of the design, and the implementation of the design, and have created mockups or put actual machinery in place with lean tools, we are set to "flip the switch" and allow value stream flow to begin in the implemented areas. Again, while we may have worked on many areas in accordance with our plan to stabilize them and prep them for flow, the "switch" connecting these areas should be flipped from the customer back to the receiving deck. Once the switch has been flipped and value stream flow has begun, a walk on the shop floor should reveal several things: