The objective is to count to 21 by following all the rules and not making a mistake.
Everyone sits in a circle and the goal of the game is to count to 21. Someone gets to start the game by tapping their own shoulder with a closed fist and counting ÛÏ1Û. Whichever shoulder the fist hits (left or right) the person in that direction will go next and tap their fist to their shoulder and say ÛÏ2Û. The only other rule that you start with is at 7 and 17 you have to put your arms up horizontally, one above the other, and at 7 the top hand points to who goes next, and at 17 the bottom hand points to who goes next (the person gets to choose which arm is on top or bottom). Once you get to 21, whoever it lands on gets to make a new rule for a pair of numbers (like 2 and 12, or 6 and 16, 8 and 18 etc). 21 is the only one that doesn’t have a pair. If someone makes a mistake, that person has to start over from 1.
Once all the numbers have rules everyone gets three chances to mess it up. If you mess up three times you are out and you continue until one person wins.
Some example of rules to make up are: instead of tapping your shoulder you can point at someone in the group, you look left or right instead of tapping your shoulder, have the counting go in the opposite direction at a pair of numbers, say something completely ridiculous while keeping a straight face and looking at who has to go next, etc.