Planned Encounters
The GM works these out in advance: when the adventurers come to this place, they meet these people (or animals, or whatever). All the important encounters in your adventure should be planned.
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Familiarize yourself with the rules for creating fronts, but DO NOT create one.

Daydream some apocalyptic imagery, but DO NOT commit yourself to any storyline or particular characters.

Everything you say, you should do it to accomplish these three, and no other. It’s not, for instance, your agenda to make the players lose, or to deny them what they want, or to punish them, or to control them, or to get them through your pre-planned storyline (DO NOT pre-plan a storyline, and I’m not fucking around). It’s not your job to put their characters in double-binds or dead ends, or to yank the rug out from under their feet. Go chasing after any of those, you’ll wind up with a boring game that makes Apocalypse World seem contrived, and you’ll be pre-deciding what happens by yourself, not playing to find out.

The one thing you absolutely can’t bring to the table is a planned storyline or plot. You don’t know the heroes or the world before you sit down to play so planning anything concrete is just going to frustrate you. It also conflicts with your agenda: play to find out what happens.

Здесь точно так же «выбираются, создаются и ввбрасываются» правила.

Но т.к. правила здесь гибкие (Александр назовет из «принципами»), это, разумеется выглядит иначе, чем «берем правила из вооот этих книг».