OK THIS IS WHAT YOU DO..... First fined some soft, wet, smelly shit. It could be cat dog or human if ur realy that intent get get revenge. ok first pick it up with gloves (recomended) or paper.
lay some toilet paper on the ground place the dump in the toilet paper. next carry to the door step or the person you hate make sure that you have raped it up tight.
set fire to the paper (the more paper used the better) ring door bell and belt (leg it, or fly like monky piss)
result: when the owner of the house comes to the door the reaction will be to stamp it out i.e treding in the shit they wont notice coz of the burnt paper then go in to the house thus spreding the crap round the house ..... hehehe have fun