Basically, you choose odds or evens and remark "Once, twice, three, SHOOT!" each player either holds out a closed fist, 1 finger, or 2 fingers, therefore the total can either add up to 0, 1,
2,
3, or
4. If it is 0, no player wins. If it is even (
2,
4) the evens player wins and if it's odd (1,3) the odds player wins.