Hi Anne,
Steve post all his patterns as a pdf file, which makes it more difficult to manipulate. If you have a program that will convert a pdf file to a jpeg file then you can take it there, save the file then upload it to the PosteRazor, here's the link
http://posterazor.en.softonic.com/ to make it larger. It's a small download and it's a small learning curve to learn how to use it. Just do what it says and you'll be all right.
Another way to do it is to print out the pattern directly from Steve's site, scan it, and make sure you save it to a file that you'll know where to find it. Then when photo razor ask you to input an image just upload the file that you saved and follow the rest of the directions.
PosteRazor will not accept a pdf file, that's why it needs to be in a format (.jpeg) that it will accept.
Good Luck
Bob
PS... Yes there are other ways to do this, but I thought I would keep it simple.