Throughout this Photoshop tutorial we'll create multiple concept designs for a consumer product that will take the form of a watch. We'll choose one of our sketches and refine it to a level where it can be presented as a final product design. We'll also create additional detailed sketches to create a comprehensive guide for us to model the watch in Rhino in the future.

By the end of this Photoshop training, you'll have a better understanding of how the concept design portion of industrial and consumer product design works.

http://www.digitaltutors.com/tutorial/1942-Product-Design-Pipeline-Concepting-a-Watch-in-Photoshop