We had a blizzard in Connecticut on Boxing Day (December 26). The traffic advisory read "Do NOT drive. If you must drive make sure you have a winter survival kit with you." This seems like a particularly perspicuous advisory in that it made it very clear what we were supposed to do, or, rather not do.
Perspicuous: "plain to the understanding especially because of clarity and precision of presentation" – Webster
NASA's Dennis Lovin took us to task for not making our book tool download pages perspicuous enough. He was right. We've made them more clear. Thank you Dennis.
You should do the same thing for your onboarding practices. The odds are things are not as perspicuous to new people as you think they are. You'll be evaluating your people on many things. Their ability to sort through obfuscated instructions should not be one of them.
How are you making onboarding more perspicuous?