In order to calculate a round robin, or a tournament with a fixed amount of participants with an equal advantage, assign each participant a number with one competitor at the fixed beginning number and all other participants rotating in one clockwise position until each participant ends up in the initial position. A simple table can be adapted to calculate the position of participants.
To create a round robin table, calculate the numbers one through x, x being the total amount of participants, minus one. To create the schedule, number vertical rows with this number and horizontal rows with this number divided in half. For example, if there are twelve participants, the vertical rows are one through 11 with the twelfth participant in a fixed position, and the horizontal rows are 1 through 6. Each participant meets the others equally until the player ends up in the initial starting position. There are round robin schedules available online to customize and print.