There is a little plastic device you use to determine were 1/4 inch will be. It's called a sewing machine seam guide. Just Google it in Google images to see what one looks like. I think I bought several at Wal-Mart within the past six months. It has a little hole which you place your sewing machine needle in and then it will measure over for you to where the 1/4 inch line (seam) should be. You can either buy a 1/4 inch foot for your sewing machine that has a blade for you to place your fabric against, or you can buy some Dr. Scholl's moleskin pad and cut a length of that to place on your machine's surface. It will work the same way.