The most important rule in darts is that players or teams must be the first to reach zero after starting with 501 points to be declared the winner. The required length between the player and dart board is exactly 5 feet 9.25 inches.
The setup of the dartboard is an important rule that dart players must be sure to follow. The bullseye of the dartboard must be 5 feet 8 inches off of the ground, otherwise the entire game is considered invalid. One of the more common ways to play darts is the "best of" format, in which the player who is the first to win three legs is declared the winner.
In order to determine who goes first, players attempt to throw a dart closest to the bullseye. The winner is allowed to throw first in the first leg and the subsequent odd-numbered legs. The loser gets to throw first in the second leg and any remaining even-numbered legs.
A player's turn, also known as a throw, can only consist of using three darts. The one exception to this rule is if a player is able to reach zero on his final throw without using all three darts. Darts cannot be rethrown, and darts that do not stick to the board are not included in a player's score.