Go to Scrollsaw Workshop site, scroll down to the Rapid Resizer on the left, read what is there and at the end click in "Resize a Pattern"
It brings up a screen yellow background, picture of Steve, little gray box. There is a browse button. click browse, (i had already downloaded a pattern to my computer).
I found the pattern and clicked on it. It lists the file just beside the "Browse" and below it is a button that says "submit my file". Click it,
It takes you to the RapidReszer site loads the file. I choose the page I want to resize, tell it what size I want and hit print.
It takes me to my print options I select "poster" and print.
It is very slow, you have to wait for everything to load before going to the next step.
Just went through it again as I wrote this and it worked. I don't know if it would make any difference, but I am using a Mac computer.