Is there a word or an idiom for the hand gesture, done after finishing a task successfully or after knocking down the opponent in a fight? The one like wiping off the dust from your hands, which indicates it's a victory but it was easy for you. Not done to gloat, just happens spontaneously as if it's a natural gesture.
brush your hands
According to local lore, when God was satisfied with Creation, and brushed his hands together, the crumbs that fell unnoticed from his fingers into the sea formed Cape Verde.
Google Books: Cape Verde Islands By Aisling Irwin, Colum Wilson