Swiss-system would be the best.
In tournaments where most Players start the event with known ratings, the Players are ranked for the first round by rating. The list of all Players is split into two halves.
The top Player from the first half of the list is paired against the top player from the second half, the no.2 player from the first half is paired against the no.2 player from the second half, and so on through the last players in each half.
The color of the top Players from each half is assigned at random and alternates for each subsequent board.
When the first round results are known, a similar method is used for the second round. Players who won in the first round are ranked by rating, the list is split into two halves, the top Player in the first half is paired against the top player in the second half, and the other players are paired accordingly. The same method is used for players who drew in the first round, and for Players who lost.
In subsequent rounds, the same method is used for all players who have identical scores. Pairings for the third round are made for the groups of players who have 2, 1.5, 1, 0.5, and 0 points. In this way the best players tend to meet each other in the last rounds, when prizes and titles are on the line. The other Players have the opportunity to play the complete tournament; no one is ever eliminated.
A few other rules are followed throughout the pairing process:
1)No player may meet another player twice;
2)Color balance is respected for each round, so that each player has approximately the same number of games with the White and Black pieces;
3)Where there are an odd number of players to be paired in a group, the highest ranked players can be moved up one group and the lowest ranked moved down to maintain balance; and
If there are an odd number of players, the lowest ranked player gets a FREE. This means that player has no opponent and earns one point for the round. Each player may receive only one FREE per tournament.
In tournaments where most Players start the event with known ratings, the Players are ranked for the first round by rating. The list of all Players is split into two halves.
The top Player from the first half of the list is paired against the top player from the second half, the no.2 player from the first half is paired against the no.2 player from the second half, and so on through the last players in each half.
The color of the top Players from each half is assigned at random and alternates for each subsequent board.
When the first round results are known, a similar method is used for the second round. Players who won in the first round are ranked by rating, the list is split into two halves, the top Player in the first half is paired against the top player in the second half, and the other players are paired accordingly. The same method is used for players who drew in the first round, and for Players who lost.
In subsequent rounds, the same method is used for all players who have identical scores. Pairings for the third round are made for the groups of players who have 2, 1.5, 1, 0.5, and 0 points. In this way the best players tend to meet each other in the last rounds, when prizes and titles are on the line. The other Players have the opportunity to play the complete tournament; no one is ever eliminated.
A few other rules are followed throughout the pairing process:
1)No player may meet another player twice;
2)Color balance is respected for each round, so that each player has approximately the same number of games with the White and Black pieces;
3)Where there are an odd number of players to be paired in a group, the highest ranked players can be moved up one group and the lowest ranked moved down to maintain balance; and
If there are an odd number of players, the lowest ranked player gets a FREE. This means that player has no opponent and earns one point for the round. Each player may receive only one FREE per tournament.