Work with a professional engineer for 4+ years. [1]
No degree PE routes exist if you work under a PE for a number of years [2]
Engineering-related such as math or physics degree can serve in lieu of engineering degree [3]
In Texas, don't even have to work under a PE, but need to have PEs certify that your work is subject-relevant. [4]. Cet licensed in Texas, transfer degree to another state.