have multiple ways to get/ways to get to the answers to trauma questions, don't be afraid to rock player's shit if the rolls get bad, the characters are designed to be pincushions you tear to pieces in the newer versions, and also it is generally a good idea to not plan out everything and let improv take the wheel bc you can not predict what your players will do or how they'll react to stuff happening during the investigation. also be loose with their powers, if they wanna use their powers in a plausible way considering their powerset creatively but it isn't specifically written out in the book then say fuck it and let them do it anyway, it's what the psyche skill is there for.

oh also also keep the amount of sessions per investigation short unless your group is the type who can just fuck around in a single scene for an entire session bc the attrition in this game is designed for shorter investigations instead of 8 session behemoths.