How to Play
The game is played through conversation. First, the Game Master (GM) describes the scene, setting, or situation. Second, either in turns or free form, the players describe what their characters do or say, and how. Third, the GM determines and describes what happens. Repeat until a scene is resolved, then the GM establishes a new scene.
How to Personify Your Character
You the player personify your character based on how you conceive them (with respect to the tone and setting of the game). Game mechanics and character statistics are just numbers. A low intelligence statistic does not mean you have to portray your character like an idiot, and nor should you portray your character as too dumb for self-preservation or as self-sabotaging. A low personality statistic does not mean you can't be effective in a conversation. It is OK to ask what you would do if you were in your character's place and do that.
How to Use Descriptions
Everyone should use deceptions like a narrator in a story. Avoid using game terminology. Use as much natural language as possible. For example, instead of saying "I use 30 ft of movement to move to the front of the troll and I use my action to attack him", say "I run across the room and swing my sword at the troll's head." Try to say everything you're doing on your turn in a single fluid sentence like reading a line from a novel.
How to Use Dice
Dice do not tell the story, we do. The setting determines the limitations of the fiction (of fantastic elements like magic). Once those limitations are established, the rest of the fictional world is assumed to default to realism as this is our common frame of reference. The difficulty of actions should therefore default to our expectations of believable reality and should not be arbitrary for the sake of game design or balance. In effect, if an action can reasonably succeed, it does. You don't need game rules, mechanics, or dice to tell you what happens. Just apply logic of a believable make-believe world. Dice are for combat and sometimes for traps.
Would my character know anything about the monster? A wizard might a few things, a ranger might now a few things, a county bumpkin might know a few things. You don't need a line item on your character sheet for this, it's all in how you can justify having the knowledge within the logic of the setting and the story. You may argue "my character is a ranger of this frontier, this monster is a common threat here, so I would know a little bit about their behavior and weaknesses." A wizard might know something about their history or lore. A country bumpkin might know a few local scary stories.
Interactions with non-player characters (NPCs) are resolved similarly, but through roleplay. Players should never say "I try to persuade him" or "insight check." Treat NPCs like real people. Say hi. Tell them about yourself. Ask about their troubles or services. Treat them as resources for news and rumors. Offer them something that will make them happy in exchange for what you want or find something that gives you leverage over them and threaten them with it. If you tell a lie, it should be a plausible one to avoid suspicion. You WILL earn a reputation that will follow you around.
There is no die roll to search a room. The GM describes the room, and additional information is revealed to the players as they describe how their characters interact with it.
Danger Should Be Obvious
There should be no sneaky tricks by the GM. No gotchas. Danger should be obvious. If player characters get hurt, it should be due to their own decisions. Listen to GM descriptions. Ask questions. You are entitled to any information that would be obvious to your character. Rely on your creativity and critical thinking.
Metagaming
Here's how I define metagaming at my table: Metagaming means thinking about the game like a game. Instead, approach the game like a roleplay exercise rather than a tactical exercise. Your character doesn't have a concept of game rules like "Sword skill +5" or "luck dice". Assuming game balance and making decisions based on that is also metagaming. Embody your character. Put yourself in their place.
"You pass through a heavy wooden door that wants to slam shut behind you and you enter a cold, cramped, stone room. The torch in your hand is your only source of light. You hold your breath and listen but hear nothing. To your left is an old dusty bookshelf with only a few dilapidated books. To your right is a small, worn looking table connected to the corner walls by cobwebs. Across the room is a messy desk with a few crooked drawers. The floor in front of the desk has new and old footprints in the dust. What do you do?"
You don't know if there are any traps or hidden dangers, and your character does not have a concept of saving throws to automatically avoid harm. Your character does not have a concept of random encounter checks either; Whatever you do, time is passing, and the longer you're in a dungeon, the more likely you are to encounter danger. Your torches are limited. They limit how far you can go. As they burn away, they give off light like a beacon and smell of smoke. So far, you think you've avoided detection by enemies, but they've left signs of their presence with their footprints in the dust on the floor. Consider that you don't know if they're already tracking you. Don't think about how many hit points you have and how much damage dice something might do. Think about the potential wounds or injuries your character wants to avoid. Getting ambushed does not mean the GM rolls a bunch of damage while you do nothing, it means you're getting shot and stabbed in the back and for a moment you're helpless. Combat might be fun for you, but for your character, it's deadly. It's not about winning or losing, it's about surviving and staying safe. Combat rounds represent a few seconds of time; Your character has to think fast and act fast to survive! Once you're in a fight, it's too late to talk strategy. Prepare first!
Rules Talk
Absolutely no rule books or rules discussion during the game. If you don't know how a spell or weapon or etc. works, the GM will tell you how it works this time. Game time is for playing. Learn or work out the rules outside of game time. All that being said, the GM is mortal and cannot guarantee rules mastery, and should use the honor code when in doubt. If a player declares and attack with a long sword and rolls a d8 for damage, we can trust they're being honest and we don't need to question that midgame. Do you have 30 feet of movement or 35 feet? Do you have a +1 or a +2? Does a torch burn for 6 exploration turns or does it burn for 1d6+2 exploration rounds? Who cares. Make a ruling and play.
No Do-Overs, No Ret-Cons
Once you declare your action, you can't change it. As they say in golf, play the ball where it lies. I know that your character would ordinarily have known to do something or not to do something, but this time, for some reason, they didn't. If you forgot something, maybe you'll remember it next time.
The Monsters Want to Win
Do not think that any fight or dangerous situation you find yourself in will be balanced and fair. That would be metagaming by the way. Assume the bad guys will fight dirty. Assume they will cheat and use every advantage. Assume no mercy. The bad guys want to survive, and they want to win with the least cost (wounds, injuries, and casualties). Fighting is deadly, and fighting fair is deadlier.
How to Make a Player Character
Character creation should begin with the character concept and end with choosing stats, mechanics and powers. Character concepts must suit the setting and tone of the game, so have a few character concepts in mind in case one doesn't work. Who was your character before becoming an adventurer, and how did they fit in the setting? Why did they give up their life to become an adventurer? Finally, what is their goal for adventuring? Some GMs consider it necessary for player characters to have goals! When in doubt, create an ordinary person who becomes an adventurer.
How to Set Expectations
General: GMs set the rules for their game, like table etiquette and general courtesy, but they also define the scope of the game. What genre, subgenre, setting, tone (mood), etc. Give an elevator pitch that sums up the kind of game you intend to run. Consider "I'm running a dark, low fantasy game in a grounded setting that is vaguely period and Mediterranean. Fantastic elements like magic and monsters are unordinary but present. Stakes are less epic and the conflict comes from diegetically occurring obstacles that appear on the player characters' paths as they pursue their own goals in play. Don't do anything you wouldn't do in real life. Play your character like you care what happens to them." Consider referring a movie or tv show that people can relate to.
Setting: Offer the players seven pieces of information their characters would know about the setting. They can be mundane, or they can be exciting or concerning news. "The King is dead. His heirs are fighting over who rules, and factions are forming among the nobility. The church has announced the appearance of a miracle worker for the first time in one hundred years. Monsters have been seen on the frontier by military scouts. Barbarian tribes who were once enemies of the empire are petitioning to join it. Rumors say that the merchant class is trying to create a revolution. Mages are leaving the empire without explanation." You don't need answers for these questions! All these ideas describe a setting where things are changing fast, and they make players wonder why. Wonder is a sensation, and it creates interest.
Create a central tension for your setting. This is an amazing tip from the Matthew Colville Youtube channel. It is a single dramatic conflict that is present in and affects your entire setting. For example, the king is dead, his heirs are fighting over who rules, and factions are forming in the nobility. Another example is that the kingdom has been conquered by another kingdom, and a new religion has been imposed on the people. Maybe the central tension is a natural disaster? This is the flavor of your setting that your players don't need to engage with. Every NPC everywhere has a different perspective on the central tension, and it forces you to consider these multiple perspectives which helps you create opportunities for conflicts. It creates a logic to your setting; All you have to do is understand this logic and worldbuilding easy and flavorful.