Does he know to inhail?
Make sure your not wasting your smoke on him if hes not gonna inhail it.
I'd say everybodies first time smoking weed is different, I didnt realise I was high. I just remember laughing my ass off for ages and thinking "what am I laughing at?".
As people have said make sure he's comfortable, dont pressure him into anything. Of course make sure hes educated in cannabis, no use getting him high if he's gonna start freaking out thinking he's gonna die or something.