A growing field in the interaction design practice is the domain of connected and interactive spaces. The idea of ubiquitous computing, that was originated in the late 1980s and the beginning of the 1990s, is now seeking maturity, and technology trajectories have helped materialize the basic prerequisites for the proliferation of spatial computing. This paper illustrates how the design process for interactive environments can benefit from an emerging set of methodologies and tools, that is the physical counterpart for the successful creation of human-centered interactive experiences in space. When creating interactive spaces, a designer needs to take into consideration new dimensions, like the flow of users within the space, the spatial context, and a new set of sensors and actuators that go well beyond screens, keyboards, mice, or controllers. Unlike other interaction design domains, there is not a defined device, like a smartphone or personal computer, but instead, the technologies of spatial computing are a collection of distributed devices, sensors, and actuators. Due to this configuration the implementation and prototyping of interactive environments requires new tools to deal with the complexity of non-standard components to ease the design process and allow for sketching in hardware and software at scale. With ad hoc software and hardware designed with the purpose of standardizing and making accessible these components, a design practitioner can implement prototypes of interactive and connected spaces to gather inspirations, insights, and validation before investing in creating the complete experience. This paper explains how the process of designing with such tools will transform the work and the outcome of the interaction designer that explores the forefront domains of connected environments, ubiquitous media, and spatial computing.