Step 1: Find yourself in a position where you must defend yourself. Telling a biker ( make sure its the kind with flies embedded in his teeth ) of how wonderful his ass looks in those tattered leather pants, is an example of an effective way to do this.

Step 2: The second that your opponent takes a fighting stance, squat, fists clenched in the air, let out a blood curdling scream and deficate in your pants loudly.

Step 3: Frothing at the mouth plunge into the nether regions of your jeans and extract the odiferous load. Make sure all present can plainly see the steaming pile in your hand.

Step 4: Generaly step 3 is all that is needed to deter anyone from harming your person. If your opponent is still compelled to attack, launch the shit bomb dead in his face. Unless he is completely mental that will squelch any further attempts on your ass.

Preperation hint: Always eat cuisine that will make your excrement extra rank. Pizza with extra cheese, anchovies and jalapenos, jambalaya, buffalo chicken wings with blue cheese, or anything with loads of grease and heavy spices is suitable.