Originally Posted by
117becca
15 /12 = 1.25. Take your 12 inch templates to a copier and enlarge it by 125%
This is how to do it, if you want to use templates. If you don't have access to a photocopier, you can also print it at 125% on your printer. You will have to make this change in your printer settings, which vary from printer to printer, though.
With 15" blocks, I would do 6 blocks across by 7 down, giving a 90"x105" quilt (without borders). This is a generous queen size, with a pillow tuck.