You might want to run a swiss system tournament. Use index cards to list a team, opponent, score this round, and cumulative score. It's random for the first round unless teams have some rank or seeding. For following rounds, make stacks of teams with similar cumulative scores and pair them unless they have already played. Continue for 8 rounds.
Swiss system is used often in chess tournaments if you want to search further or buy software to pair and help run the tournament.