easy...
id kill all people i deem scum. pedos,other serial killers,rapist, people who rob other people.
id first make a mold mimicking a knife. then id fill it up with water until it froze, and sharpen the edge/point until it's ready to be used for killing. after i commit the murder with it, it would melt away. no DNA or evidence. wear fake dreads ( id cut off my real ones) and a beard with shoe lifts to throw off police/cameras etc.. and i wouldn't tell anyone.
it's pretty easy to get away with murder.