This is how I would suggest running Itras By.
Know the rough outlines of the setting, and communicate it to the players
Itras By can sometimes veer into the absurd-but-not-in-a-good-way. The setting is part of what gives the game coherence. Communicate it to the players before play (the rich folks are over here, the working class is down here, reality dissolves that way). And during play (you see the Moon Tower on the horizon, the fog floats eerily over Church Hill, etc).
Use the players’ ideas!
The character creation process in the game produces a ton of ideas, saving you much prep time. Use this information. Use their NPCs and the relationships they’ve defined. Make sure their Dramatic Qualities see playtime. The players will be more invested in the game when you use their own ideas and concepts. It’s better to read the character descriptions two or three more times than to spend time preparing a “plot”.
Keep prep simple
Read the character descriptions. Make a relationship map including NPCs. If you have the time; jot down ten or so sketches for scenes, cool situations and places you’d like to explore. You can also crowd-source a few such sketches from the players.
Follow standard improv method
Say yes unless there’s a particularly interesting reason to say no. Build on what has been established in the fiction. Reincorporate. Follow the first idea that comes to mind. What seems obvious to you can be interesting to others. Cut floundering scenes.
Follow the few rules there are for the cards:
When something important is at stake, consider a Resolution Card to decide the outcome.
The player states what their character tries to achieve. They appoint another player to draw and interpret a card.
· Anyone can suggest drawing a card.
· Roughly one Resolution card per scene.
· Try to resolve consequences before introducing many new card-twists.
When you want to inject an element of surrealism, draw a Chance Card.
They interpret its effects themselves. It’s fine to ask for ideas. When the card is drawn, its instructions should be followed. The Chance cards can bring heavy tilts to the story; each player can draw one Chance card per session, at any time they like.
Divide labour, while remaining conductor
Ask players to play NPCs for each other. Ask them to set scenes, ask them for details about the setting. Take in their ideas, ask for input. But remain a solid conductor of the orchestra. Maintain some coherence to the story. Shine the spotlight around. Cut scenes that are not going anywhere.
Make it real
Aim for a balance between everyday, realistic, scenes and the high weirdness that inevitably follows from setting, cards and character quirks. Juxtapose these. Also: help make the characters believable. Use the emotions of the characters and the immersion of the players to give weight to the story. Create an atmosphere of trust. Allow the players to take the story seriously. There is a lot of humour in Itras by, but it shouldn’t be non-stop silly.
Tie it up
The cards makes it impossible to script a game of Itras By. Don’t try to. But help the players tie the various threads of the story together toward the end of the game. Aim toward satisfying conclusions. Reincorporation is your best friend here, re-using concepts and ideas that have occurred earlier in the session, making call-backs.
Nørwegian Style 
