How do two casual players decide who plays Red when there is no tournament pairing to sort it out?
These answers restate the rules implemented by our open-source engine, which follows the WXF laws and is regression-tested against the official 110-diagram repetition casebook. Where an answer refers to a specific position, that position lives on the linked reference page, where the build verifies it against the engine before publishing.
Direct answer
However they like, informally. A coin flip, one player hiding a soldier of each colour in closed hands for the other to pick, or simply agreeing to alternate colours from one game to the next are all common ways two casual players sort this out. Nothing in the rules governs it outside formal competition.
Why it barely matters in a casual setting
Red's first-move edge is real but modest, and it is dwarfed at casual and beginner level by whoever happens to hang a piece first. Spending more than a few seconds negotiating who gets it is rarely worth the trouble compared with just getting on with the game.
What to do over a series of games
Alternating colours each game, or each session, is the simplest fair approach if you are playing the same person regularly, and it means neither player needs to think about it again once agreed. Formal tournaments handle this with pairing software instead, but nothing that elaborate is needed between two friends.
Related questions
Does it matter who chooses first in a casual game?
Not really; any agreed method that feels fair to both players is fine, since nothing formal is riding on the result.
What if we just want to play without worrying about it at all?
Take turns starting with whoever asks, or simply play Red every other game by default; either is a completely normal way to handle it casually.
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