I used this exact tutorial when I made my colorwash quilts. However, I drew my own lines on a very lightweight interfacing. Talk about tedious. You have to be careful not to stretch the interfacing especially if you are joining pieces of interfacing together (because it's only 22" wide). I also trimmed a fraction of an inch off of each square. This made the sewing process much easier for me. Here is the result:
http://www.quiltingboard.com/picture...t-t225974.html
I tried to upload a pic of what it looked like right before I sewed but the file upload failed. I'm not patient enough right now to stop and figure out what amiss! Gotta get back to my current project!
