Bring your own white board, ask the to bring some fogging estandards.
But seriously, it depends on where they’re at so far – do you need to explain offside to them (don’t even try to explain handball) or are we talking tactics? For the former, I would tell them what player or two to watch on the other team, and point out that our beautiful blond #8 is going to try to move the ball around until he has a chance to link up with 7 and 11.
I’ll stop there and add more in a comment if you think they really want to be thinking about tactics.
I trust Arteta and all, but it’s really nice to see Saka playing more than 3 yards away from the touchline