Фан fiction help?

I'm Письмо a Хеталия Фан fiction, and I need a little help on how to start it. It's pretty much about England going crazy and killing people with Russia and France. He also tries to kill France. I would also like to include EnglandxFrance, AmericaxCanada, RussiaxChina, and LithuaniaxPoland.
Thank you!<3