> I find I'm constantly saying "wait go back what did the output of that command say" or "wait that error message doesn't make any sense based on what we changed last time, why is it that error?"

Along those same lines, I like to use the phrase "sanity check" a lot. It's meant to imply nothing should be wrong yet but we can't rule anything out, so let's check every single step and make sure they match our expectations.

For me it seems to work to get the other person to explain what they're expecting as they go through the steps (forcing them into rubber-duck debugging with me as the duck), and many times has caused them to find something they were just glossing over before without me even having to point it out.