Snooker Rules

The first player plays from on or within the lines of the D. The cue ball shall strike a red as the initial stroke of each turn, until all the reds are off the table. For the next stroke of the turn should a legal score be made,
the cue ball shall strike a colour. The game continues by pocketing reds and colours alternately in the same turn. If the striker fails to score or fouls, his turn ends and the other player plays the cue ball from where it comes to rest unless it was jumped off the table, in which case it
is played from any unoccupied part of the D.

If the player making the first stroke fails to hit a red, the other player receives the penalty for this foul and plays his first shot from where the cue ball came to rest on the table. Each colour potted or jumped off the table must be re-spotted before the next stroke until finally potted. It is the responsibility of the striker to ensure this happens but he scores all points made in that turn until the non-striker claims the foul. No foul is
awarded if the improper spotting is noticed during a later turn.

If the player lawfully pocketing the last red pots with his next stroke a colour, that colour is re-spotted. Otherwise reds being off the table the colours must be struck by the cue ball in ascending order of their values
and are not re-spotted if lawfully potted. A player must, when asked, nominate what colour ball he is aiming to play and must always, to the best of his ability, endeavour to strike the ball he is on.