I’ll assume you guys know about GNS theory. No? Well then I get to write that rarest of sentences: 1d4chan is useful here.

More than any one style of play, I think the biggest hurdle in the world of tabletop RPGs is getting everyone to inhabit the same mental space. Suppose your GM announces to the table that an enormous spider is descending from the ceiling. Bob the noob assumes that it’s real-world enormous and declares that he steps on it when it gets to the floor. You on the other hand are an experienced gamer, and you know that Shelob is about to tap dance all over Bob’s spine. It’s a simple example, but the principle applies to everything from room configuration (“I thought the sarcophagus was standing upright!”) to the famous Dread Gazebo.

These games are all about communication. As a GM you’ve got to explain your situation clearly, and as a player you’ve got to ask follow up questions. But for all our sakes, and most especially your character’s, don’t ever argue with the GM. That’s the surest way to make rocks fall.