The Crimson Binome
Hero
Treat the world like a living world. Place NPCs and monsters where they make sense, based on how the world works, rather than what you think would make for fun encounters based on the party or their levels.Funny, I thought meta-gaming was a bad thing players did, not DMs. If you expect the DM not to think of the game as a game, I'm not sure how that would work.
As DM, you are the laws of nature, impartial adjudicator of all things. You have no objectives, other than to honestly present the world and its inhabitants. You aren't trying to run the PCs down any particular path, or make them jump through any particular hoops. Any conflict or drama that happens around the PCs ("on-screen") is just a byproduct of your honest presentation of the world, the characters, and their goals.