I play in several groups of people with very different backgrounds of experience and willingness top deep dive rules.
My main game is mansion of madness. Not the most complex one, but already several hours long with some crucial rules. The game does not need a dedicated game master as that part is done by an app. But the game pieces, cards are physical objects.
I did two things to improve the game experience for every one.
First, the organization of all cards, objects, board material. I have put every thing in labeled boxes. The card are grouped by type and alphabetical sorted . This really really helped a lot to speed the game up. And often there are only marginal waiting times to find things. So the players are way more focussed on the game.
Second, I adapted my play style a little bit. As it is my game, I'm often the Referee and solve ruling question. So I can confirm that often by owning the game you often are the unofficial game leader or game master.
But if I play in a group with experienced players, I can get them involved. As I have everything in boxes, i can easily say: you are in charge of these kind of items and place the box in front of them. Another player for this kind of tokens. For each other player it is only one type of material with it's rules. But for me I can remove several parts of the rules from my responsibility.
If I play with a group nearly completely with first time players, I sometimes don't play with them, instead completely focus on the role of game master. It works for me with this game, as it is very interesting to see how my friends behave in problem solving situations or how they solve the puzzles. And in this case I can focus on explaining the rules to them. Check on their train of thoughts. And with this "training", after the second game the other people are fit to overtake simple tasks.
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