This work in progress continues an ongoing project to understand and document engineering students' innovation identities. Prior studies have reported on how students separate their engineering and creative identities, on demographic differences in students' ideation processes, and on students' description of barriers that prevent them from practicing engineering more innovatively. Using process maps drawn by 32 undergraduate engineering students, we perform an inductive qualitative analysis of students' innovation process maps. We look specifically at features and characteristics that are common and different across the process map artifacts produced by students. The result is a coding protocol that researchers can use to characterize process maps or explanations of the innovation process. Future work will extend the coding protocol as a tool for assessing students' conception of innovation.