Each person creates their own unique 'sign' - a discrete action such as the peace sign, thumbs up or down, pat on the head, tap on the nose, etc. It shouldn't be too obvious or attract a lot of attention.
Everyone sits in a circle facing inwards and demonstrates their sign to the group.
The aim of the game is to keep passing signs to other players as long as possible, without getting 'caught' by someone who is standing in the middle of the circle. The person in the middle has to guess who currently has the 'sign' or catch someone mid-sign.
To start, the person in the middle closes their eyes, spins in a circle and counts to ten. During this time, one person (person 1) starts by doing their sign and the sign of another person (person 2). Person 2 then passes the sign by doing their sign and then the sign of another person (person 3). This process continues until someone is caught - that person then becomes the person in the middle.