This paper presents a tool to transform a smartphone into a smart eyewear, named "CARTON", following a Do-It-Yourself (DIY) approach. The hardware prototype is made with very simple materials and regular tools we could find anywhere. It also includes a Software Development Kit (SDK) with samples in order to easily adapt or develop new mobile app compatible with this kind of device. By providing everything open-source and open-hardware, we intend to solve the reachability of technologies related to smart eyewear and aim to accelerate research around it. Users experiments were conducted in which participants were asked to create, by themselves, the CARTON's hardware part and perform usability tests with their own creation. Qualitative user feedback and quantitative results prove that CARTON is functional and feasible by anyone, without specific skills.