i know that if somebody's giving me direction to do something but it's not something i fully know how to do and their directions are really really vague, i sometimes don't know where to start.
if it involves multiple steps, allow them to write them down, and be as clear as possible. i do think this has to do with short-term memory issues.
even following a clear list can be frustrating cuz it takes a long time to go over all the steps and make sure everything was done correctly and nothing was missed.
saying something in a way that sparks interest helps. i can't explain this, other than "don't be boring" (and this isn't very helpful, sorry). maybe see if there's a way to make the task more engaging? sometimes not possible if you're asking for something that's tedious by nature, like doing a chore.