Yeah it took me a while to figure it out, but I DID! So for me and you and everyone else going “wait wtf just happened????” I present a more step by step breakdown!
So you start with a grid with as many squares as needed to write one number across the top and one number down the side. And draw these diagonal lines through them. Yes you should extend them out the side.
THEN you basically multiply the numbers that match with each square, put the tens digit in the top triangle and the ones digit in the bottom triangle. Like so:
so once you’ve done that, you start adding up the numbers in the DIAGONAL column/row thingies from the bottom right up to the top left, like so:
You only want one digit (tho I assume if the very top/last row somehow gets 2 digits that’s ok, but ONLY in that position) and you’ll carry over to the next column, like if you were adding normally.
Then you start at the top left and just take all the numbers going down and around and put them together!
It does take up a lot more space and has a few more steps than the more traditional long multiplication, I think, but for people who struggle with that I think this would be a handy tool!
Here’s a screenshot of the more traditional style to compare:
I hope this helps! I had to figure it out on my own bc I was never taught this either. :)