Whatever number of players you choose, each player will play the same number of matches. Most times, it is best to choose a number that you can evenly divide by 4. Then each player plays every round, and no one needs to pass. In addition, all players will play with all other players exactly 1 time, and against all other players exactly 2 times. The same applies with 1 more player (5, 9, 13 ...) but then all players will skip one turn. For all the other number of players, each player does not play with or against all other players. But the number of matches is the same for everyone.