How do I write a History essay?

I have a History essay due next Tuesday. I haven’t started yet because I don’t know where to start – I have never written a History essay before and so it is very difficult for me. I want to start doing it now because I also have an English essay that is due next Wednesday. The History essay has to be 1000 words long.
This is what I am supposed to do:

Essay assignment 2 Essay title : ‘Discuss the short and long term consequences of the Indian Mutiny 1857.

I have the book and I have already read about the Indian Mutiny but I will read over it again.

thanks in advance!