First of all- if you give a shit about your father then forget about blackmail... it's only going to fuck things up more.

Give whatever evidence you have to your dad.
Let him decide what to do.
DO NOT let her know whats up.

Think of this like a job. In most decent jobs if they have to let a person go (for any reason) then they fire that person and give them at least two weeks pay. They don't tell a person "ur fired bitch, be out of here in two weeks." The reason being is because that person can really fuck some shit up in two weeks time. If you let your dad know whats up, then he'll have the time he needs to prepare (cancel the credit cards, move some cash around from bank accounts... you see where i'm getting at). If she knows shit is about to go down she could really fuck shit up for you guys.
BigHomie Reviewed by BigHomie on . What would u do if u ever caught ur step mom cheating? Ok lets just ur step mom is 40 and is caught nailing some 25 year old employee in ur bed.... She is very strict with u, never lets u smoke pot or do drugs for that matter... And says sex b4 marriage is wrong.... U have photographic evidence that she was doing it... How would u blackmail ur step mom into doing what u want? Rating: 5