dude..more simpler...just somehow make them drink gasoline, maybe once you tell them that they just drank gasoline they'll start thinking of how bad a mistake it was to fuck with you, then you see her crying and you can see her last words as she starts vomiting you will need to make her drink more gasoline so it kills her completely, maybe as she is vomiting lay her on her back so she can choke on said vomit, then make sure it looks like she choked on her "coffee" and make sure you leave no evidence...then move on to the next girl and when complete change your name, move out of the country, and bask in the sweet........sweet revenge
you're welcome in advance