20 guests, 4 different games, different partners

[jstroble]

I am having a party and with 20 guests and we would like to play 4 different games (pingpong, darts, billiards, cornhole) so I know we would have 5 rounds with 4 people at each game, with each person sitting out one round. But could someone show me how to mix up the group so the same people don't end up in the same group or with the same people more than once?

[Ian Wakeling]

It can be done like this:

    ping-pong       darts       billiards    cornhole       sit out
  (18 11 10  3) (19  5  8 15)  (1 17 12  7) (20 14  2  6) ( 9 16 13  4)
  (19 12  6  4) (20  1  9 11)  (2 18 13  8) (16 15  3  7) (10 17 14  5)
  (20 13  7  5) (16  2 10 12)  (3 19 14  9) (17 11  4  8) ( 6 18 15  1)
  (16 14  8  1) (17  3  6 13)  (4 20 15 10) (18 12  5  9) ( 7 19 11  2)
  (17 15  9  2) (18  4  7 14)  (5 16 11  6) (19 13  1 10) ( 8 20 12  3)

note that if you divide the 20 people in to teams of 5 as follows:

team 1= 1-5
team 2=6-10
team 3=11-15
team 4=16-20

then each game has one member from each team.