Help?

Well I think I now need some help and advice from readers of this blog, yes I do have some :-).

I am trying to work out how to do Elo and Poisson spreadsheets. Now I have been searching high and low and have yet to come across something that explains in plain english how to actually work it out. I was never any good at math at school and a screen full of symbols just makes my head hurt.

Elo

This one is easy enough as there is information out there on how to do it and its straight forward and easy. Though I have only one question. Now you may chuckle when you hear it, I think I know the answer but I'm just confirming the fact before I go through my sheet and spend ages working all the ratings out. Right here goes.. If the game finishes in a draw then goal difference is obviously 0. Now then I believe that the ratings for the teams don't change.

Poisson

This is the trouble maker, I can't find anything that I can actually understand. As soon as I get to the formula section my mind goes into mental shutdown thanks to all the scribbles. Has anyone got a link to anywhere that helped you work it out?
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