At this stage you just have an initial concept of your solution, some sketches or basic prototypes, but still a long way until you have a working solution. The good news is that during the previous phase you have made sure that you have a solution that is interesting to your customers. The Design stage is intended to design and develop the previously selected solution and prove its feasibility. In this stage a big part of the technical development of the solution is done.

The design process will start by defining the requirements of the solution which will come from the idea brief, the design features of the solutions defined in the previous stage and other engineering or commercial inputs. These requirement will be used as the criteria for the technical decisions to be made during the design. Once the requirements have been defined, the actual design of the solution will be started. The great majority of products will require a 3D model of the solution using a CAD software (Computer Aided Design) but in some occasions a combination of detailed sketches and 2D drawings will suffice (i.e. cut and sew products such as backpacks). Unless you have the technical skills, most likely you will need help from professionals for this task. Depending on the characteristics of the product, you will require different type of professionals, such as Industrial Designers, mainly for concept design and aesthetics; Mechanical Engineers for technical design and materials structure; and Electrical Engineers for electronic components design and selection. This is just a very simplified list of the typical professionals and their skills, but there are many other specific professionals for particular areas and technologies (Material mechanics, plastic injection, fluid dynamics, textiles, …) and oftentimes they have skills that overlap between them. This is why choosing the right professional is crucial and evaluating their expertise beforehand becomes an important task.

As in previous exploration stage, during the design phase you should target for a prototype that can be built at the end of the process. This prototype will be a higher fidelity version of the previously made mock-ups but should be strictly focused on showing the main value of your final product with just the essential details and features. Based on your target, you will be looking at building one of these two types of prototypes; “looks-like” prototype (focused on the aesthetics, fit and form aspects of the solution) or “works-like” prototype (focused on the mechanical and/or electrical function of the solution).

As mentioned earlier, it is important to have a clear understanding on how the product requirements are being satisfied during the design and development. Here is where testing comes into play to verify your design decisions against requirements. Most of this tests will be performed on the prototype itself, whether it’s a physical test, a usability test with real users or a market test. All of these tests results will provide valuable feedback to verify if your design meets the initial criteria and it’s ready for the final stage.


You will most likely go through a few iterations of the design phase until you get your solution right, but once you have verified your main product requirements you can focus on building your product. This stage will require most of the investment in terms of cost (depending on the exact product you are building), but you should have a clear picture of what the costs of your product looks like from the previous stage. If you don’t have your own sources to cover the manufacturing costs, this is a good opportunity to help you fund these costs by using the prototype made during the design phase and show it to potential investors or use it in a crowdfunding campaign.

At this stage you are looking at refining your product design to make it ready for manufacturing or production at a large scale. There should be no substantial changes to the design locked previously and you will be looking at setting up your supply chain and manufacturing activities. This stage requires a good understanding of manufacturing processes, supplier sourcing and quality control. While some suppliers can help you setup the manufacturing and quality control, finding the right supplier and understanding how they will manufacture and control the quality of your product is still part of your due diligence. Find the right help at this stage if you are not familiar the whole process since this can jeopardize the success of your product.

This is an overview of the activities that should take place during this phase:

  • Finalise the product design of the different components and assembly. Each manufacturing process have certain design restrictions that have to be implemented into the CAD models and drawings (i.e. draft angles, minimum radius, …).

  • Build a working prototype. It is recommended at this stage to build a final high fidelity prototype (aka. Engineering prototype) which is representative of the final product in terms of aesthetics and functionality. While this prototype can be costly, it can help identify critical issues and save you a great deal of costs in tooling modifications down the road.

  • Complete the technical documentation, such as a Bill of Materials (BOM) with the list of components of your product, a Design For Manufacturing (DFM) to assess the manufacturability of your product and components and a Quality plan to define the quality controls to be implemented during manufacturing.

  • Supplier selection. Decide where you are going to manufacture your product, either locally or overseas depending on the characteristics of your product (labor intensity, technology, production volumes, logistics,...). Make sure to have a Non-Disclosure Agreement (NDA) ready to be signed by potential suppliers before disclosing any information of your product.

  • Kick-off tooling. Once suppliers have been selected and the design freeze, any tooling required to manufacture the product should be started which in most cases has a long lead time of several weeks.

  • Perform Design Validation. This is a formal testing plan for your final product. While some of the testing performed previously on prototypes could be enough, this testing is normally performed on parts produced with final tooling and production methods.

  • Validation builds. Different industries use different terminology to describe the different phases leading to mass production, mainly known as Engineering, Design and Production Validation builds (EV, DV & PV). During these stages, short runs of a few tens, hundreds or even thousands of products are build using the intended mass production setup. Any issues are resolved and the process is optimized during this stage before ramp up and mass production.

The above activities describes briefly all the effort that goes into this Build phase. There are many important aspects to be considered for each of those activities and it is a lengthy process to get the product ready for manufacturing. Fortunately, there are many valuable lessons that I’ve learnt along the way and I’m happy to share with everyone interested to listen.


Hopefully you’ve got an overall understanding of what is involved in bringing your product idea to life. Despite not being easy, building a product is being done everyday by inventors and entrepreneurs like you, so it is definitely achievable. A good understanding of the whole process beforehand and knowing when to get help and guidance will help you to achieve your vision.

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Time to build your product!

About Jesus Marti Palop

Jesus is an Industrial Engineer with more than 10 years of experience in developing products for several companies in different countries around the globe, Spain, France, China and Australia. His experience spans across different industries such as Automotive, Consumer Electronics, Textile soft goods and Medical Devices. In those experiences Jesus has gained extensive knowledge in the full product development process from concept to manufacturing, as well as industrial operations and supply chain management .