Open source hardware isn’t that easy. It is actually a mix of a bunch of different elements covered by a bunch of different types of IP. That means that you are probably going to need to pick a few types of licenses for a few different parts of your hardware.
OSHWA is working on building a tool to make this easier to figure out, but in the meantime I wanted to throw up a quick post setting up a bit of a framework. This framework is largely based on the work that Ryan Lawson and Adam Alperowicz did as students at the NYU Technology Law and Policy Clinic, although all errors are entirely mine.
The videos from ORConf 2017 are now online including this talk about hardware licensing: