Standards and existing literature provide guidance regarding methodologies for symbol comprehension testing, but practical guidance for the practitioner conducting this type of testing is scarce. This paper shares observations and experiences gained over the course of multiple symbol testing projects. Specifically, the paper addresses pros and cons of written vs. oral questionnaire administration and resulting comprehension scores, sample size and the concept of “statistical equivalence” to ANSI Z535.3 criteria, various participant recruitment methods and interview locations, and the importance of explaining the context in which a symbol appears. The lessons learned and tips provided in this paper begin to fill the information gaps that practitioners encounter when making numerous design, methodological, and practical decisions required for safety symbol comprehension studies.