Simple answer: I don't. I bring whatever all-comers list I brought and the newbie faces that. Of course, I don't run netlists... which means sometimes hardcore players don't know how to cope with what I DID bring, but that's another subject.
What I DO is get over on the newbie's side of the table and explain what I'm doing step-by step, and why I'm doing it. From terrain placement to deployment to maneuver to shooting to charge/pursue/reform options, I explain what benefits I gain from doing it.
Now I usually don't go all-out
tactically against a newbie. I tend to adopt a more straightforward battle plan... but with enough little maneuver shenanigans to show the newbie that maneuver MEANS something in the game. I'll also leave an opening or two to see if the newbie spots it... and manages to exploit it effectively.
If the newbie asks, I'll happily give advice as well, and warnings (Are you SURE you want to charge your knights into my Executioners? Are you sure you don't want to shoot the cannon at the monster?) are standard fare. But I'll also let the newbie play his game the way he wants to.
After all, the burned hand teaches the best...
It seems to work okay. I haven't had a newbie quit the game after playing me yet, and most thank me for the tactical instruction.