Which side does the king go on when setting up a chess board?

The king goes on e1 for White and e8 for Black, next to the queen and between the two bishops. An easy way to remember it: the queen takes the square matching her colour (d1 is light, d8 is dark) and the king gets whatever is left, which means the white king starts on a dark square and the black king on a light one.

Does it matter if the chess board is the wrong way round?

Yes, though not because the pieces move differently. Turning the board ninety degrees flips the colour of every square: h1 and d1 both go dark, so the queen no longer starts on her own colour and the bishop you call light-squared is standing on a dark one. Every diagram you look at afterwards is colour-reversed, which makes learning openings and mating patterns needlessly hard.

Which colour goes at the bottom of the board?

Whichever colour you are playing. Each player sets up their own sixteen men on the two ranks nearest them, so White sees ranks 1 and 2 in front and Black sees ranks 8 and 7. The coordinates never move: a1 is always the same dark corner square, it just sits on the far left from Black's side of the table.

How to set up a chess board

On a Saturday morning in a school hall I will turn three or four boards round before the first round starts, and it is always the same corner that gives them away. The square nearest your right hand has to be light: h1 if you are White, a8 if you are Black. Article 2.1 of the FIDE Laws puts it in exactly those terms, and the shorthand every coach repeats is “light on the right”.

The correct starting position, seen from White's side. h1 in the bottom right is light, a1 in the bottom left is dark, and the coordinates run a to h left to right.

Then fill the back rank from the outside in. Rooks in the two corners, a1 and h1. Knights beside them on b1 and g1. Bishops next, on c1 and f1. That leaves d1 and e1 for the royal pair, and the rule that settles which is which is the queen’s: she goes on her own colour. The white queen takes d1, which is light. The black queen takes d8, which is dark. The kings get the squares left over, e1 and e8, and so the white king starts on a dark square and the black king on a light one.

Pawns then fill the whole of the second rank, a2 to h2, and Black’s fill a7 to h7. Sixteen men a side, thirty-two on the board, and the two middle files line up: queen opposite queen on the d-file, king opposite king on the e-file.

“Queen on her own colour” survives even when a set is not black and white, which most sets are not. A cream and walnut set still has a light square and a dark one, so the cream queen goes on the light d1 and the walnut queen on the dark d8. And if your board has the coordinates printed round the edge, the whole thing is settled before you touch a piece: put the corner marked a1 at your bottom left and you are White, sitting the right way round, with the pawns you are about to place all on rank 2.

Black sets up the same board, seen from the other end

Nothing is mirrored piece for piece. Black’s rooks go on a8 and h8, knights on b8 and g8, bishops on c8 and f8, queen on d8, king on e8. What changes is only the view.

The same position from Black's chair. The near right corner is a8, and a8 is light, so the rule holds for both players at once.

This is the point beginners miss when they play over the board for the first time after learning online: a8 is light, so Black’s near right corner is light too, and both players can check the corner without moving anything. The coordinates themselves never turn round. a1 is that dark corner square for the whole game, whichever side of the table you are sitting on. If the file and rank names are new, ranks, files and diagonals takes ten minutes.

The two mistakes, and how to spot them

The first is a board turned ninety degrees, so a dark square sits in the right-hand corner. A whole game can go by without anyone noticing, because the error is symmetrical and both players have it. What breaks is the colour of every square on the board. d1 goes dark, so the queen is no longer on her own colour. h1 goes dark. The bishop you have learned to call your light-squared bishop is running along dark diagonals, so every book you open looks colour-reversed and the whole vocabulary of weak squares and opposite-coloured bishops points the wrong way. Fixing it takes two seconds. Look at the corner by your right hand and, if it is dark, turn the board.

The second is the king and queen swapped, which is far and away the commonest error in a school hall.

Wrong. The kings are on d1 and d8 and the queens on e1 and e8. The white queen is now on a dark square, and both queens have wandered off the d-file.

Two tells give it away instantly. The white queen is standing on e1, a dark square, when she should be on her own colour. And the queens are no longer facing each other down the d-file. Either check catches it before a move is played, which is why I make children point at the two queens and say “same file” before they start.

Set up like that, a game is playable but nothing you have learned applies. The f7 square is no longer the weak one beside the king, castling lands the king on the wrong squares, and the standard opening moves stop making sense. Article 7.2 of the FIDE Laws deals with both errors, and it treats them very differently. A wrong initial position means the game is cancelled and played again from scratch. A board placed the wrong way round is milder: play continues, and the position is simply transferred onto a correctly placed board.

A ten-second check before every game

Right-hand corner light, queen facing queen down the d-file, and you are done: go and worry about what to play on move one instead.