How can I pass as a teenage boy and get away with it?

I'm a 16 year old girl, I'm pretty-ish, happy with who I am! but.... this halloween I want to prank ALL of my friends! I want to try and pass as a teenage boy for my sisters halloween party and I don't want ANYONE to know that its really me!!! How should I dress? What should I talk about with my guy friends? Should I try and swag? Do you think I can pull this off without my friends thinking I'm a total freak? or should I try a different prank???? Please help haha