Three different groups turn up to an amateur event, and they are worth telling apart.
For the second and third groups the format works well. Do not mix the first group in: sit them at a separate table with somebody explaining the rules, and in an hour they can join.
Only a system where nobody is eliminated is suitable. A lost game must not mean the end of the evening - otherwise half the field goes home after round one.
It is the self-sorting by score that makes a Swiss friendly: by round two a beginner is playing an equal rather than a club player.
Blitz is a bad first experience: they have no time to think, lose on time in a perfectly good position and leave with the feeling that chess is not for them.
Use 10+5 or 15+10. The increment matters more here than in any other format: it stops somebody losing a won game to the flag - about time controls.
Show them how the clock works, separately. For somebody seeing one for the first time it is not obvious. Two minutes at the opening saves a dozen questions in round one.
The single most effective device: everybody plays in one event, but the prizes go in two categories - the overall standing and a beginners' standing. The beginner competes against people like themselves while still getting games against stronger players.
How to decide who counts: self-assessment at registration («first time», «played as a child», «trained»), the absence of a rating, or simply the number of events played. Precision is not the point - the point is having something to compete for - a field with unrated players.
Put the definition in the regulations: arguments about «why is he in the beginners' section» are settled by a criterion announced in advance.
An adult does not want to feel like a pupil. So the explanations are framed not as a lesson but as a reminder of the regulations.
In the Vibe Chess app a first-timer keeps a game history, their own rating and a list of upcoming events in their city - which is a reason to come again in itself - why people stop coming.
A Swiss: nobody is eliminated, everybody plays every round, and opponents are matched by score, so by round two a beginner is playing an equal. A knockout is the worst option - half the field leaves after one game.
10+5 or 15+10. Blitz is wrong for a beginner: there is no time to think and they lose on time in a good position. The increment is essential - it prevents a won game being lost to the flag.
Add a separate beginners' category: one event, prizes in two standings. Decide who qualifies by self-assessment at registration or by the absence of a rating - precision does not matter, having something to compete for does.
Briefly, and as a reminder: touch-move, how the clock works, en passant and castling. Do not correct people publicly during play - walk over and say it quietly at the table.
Do not put them straight into the tournament. Explain the rules at a separate table and offer them either a later entry or the next event. A casual meet-up with no standings is a far better first experience.
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