Find a railing and sit your ass on it and press hard against it and don't move. If no railing, against the wall also can. Press very hard against it. Empty your mind and don't even focus on rushing to the toilet as that will make the shit come out faster. Breath slowly and close your eyes. When you feel that the shit is subsiding a little, walk a few steps slowly. Keep repeating this process till you find the nearest toilet. Make sure you continue to hold it in till you enter the toilet cubicle, close the door and unzip and pull down your pants and underwear with your butt above the toilet bowl and then... BOOMMMM...!!! Depending on the intensity of the explosion, the whole toilet bowl and the walls will be a total mess! Even your pants and shoes might be stained when the shit splatters all over. When you have cleaned up the mess, quietly sneaked out of the cubicle. Let the cleaning aunty handle the mess!