I'm an old school type engineer. When I design something I usually try and build a mock up of the unit. The other thing I did was to work in the environment the design is for to get a better understanding of what is needed and what is not. When I wanted to do architecture I got a job in house construction, that way I understood the building requirements and limits of building on site. Think of ways to limit complexity of the construction and ways to reduce costs via materials or labour.