Running euchre for 10
For 10 players you will need 2 tables, 2 euchre decks (9 up to ace), and 3 sheets of paper for the score cards (four to a page). With 8 or 12 players nobody would sit out.
Give each guest a number as they arrive. Each round, find your number: the pair before the "v" sits North and South, the pair after sits East and West, so partners face each other. Many parties play 8 hands a round, then everyone writes their team's points on their card and moves when the host calls time.
Sit-outs can't come out exactly even over 9 rounds: 2 people sit out once and the rest twice. Play 5 or 10 rounds if you want everyone to sit out the same number of times.
Each score card lists that player's table, partner and opponents for every round. Want names on them, a different number of rounds or a fresh shuffle? Open this chart in the planner.