Tell him beforehand what, and most importantly, why he'll be doing whatever tasks you give. The biggest issue I had was the lack of explanations for things when I joined my first job. "Set yourself a local Linux server environment in Virtualbox, see you in 3 hours", without any idea what it'll be used for. Then my supervisor comes back, saying "why exactly did you install these specific distributions when you should've installed x distribution for your upcoming tasks obviously". And it was by no means obvious that said distro should've been chosen. His explanations for everything were always way too vague, and whenever you'd ask for more specific information, he'd just give you this dumb look, like "why the fuck would you need to know that".