TinyHomeDIY is a resource wiki for building your own tiny home. It's 2017 and there is a ton of quality info for planning your tiny home, right here online. The most practical sources are blogs by individual builders who detail their decision-making processes, materials, methods, costs, and the problems and solutions they encountered. Distilling all that knowledge with common sense should result in a DIY master plan that's as close to foolproof as humanly possible. That's the attempt here, to synthesize, giving full credit and sources.
A master list of building steps, once you have plans in hand (in progress). At the moment, this is for a trailer-based house, steps 1-3 will be adjusted for a non-trailer build.
List from Erin & Rob build a Tiny House: Building Checklist
From The Tiny Life: Tiny House Building Checklist