1.)an open palm slap to the chest, concidered "the normal shammy"
2.)an open palmed forewards thrust to the chest, or the "power shammy"
3.)a dead finger slap to the chest
all of which you shout "SHAMMYWANKSTER" while performing
But once iniciated, the circle of shammy continues endlessly, causing paranoia and nervously protecting ones chest.
Also, as of now there has never been a femal-shammy, for obvious reasosns
boy #2 "SHAMMY WANKSTER!" *slap*