I have to write an essay for American School of Corr. and I don't know where to start...?

I've read through a lot of the questions regarding homework, and I'll say right off that I am not looking for answers or a way to cheat. I'm self-schooled, uninspired and just looking for a little guidance. I'm writing a compare and contrast essay on the the peoples of Bangladesh and Pakistan (the subject is World Geography) But for some reason my mind freezes up every time I sit dow to write it. If anyone can give me a few ideas, or chat with me a bit to help me work it out, it would be greatly appreciated.