Step 1: Lay out your embroidery and figure out where you would like the hem creases to be. Pull a thread out of the fabric at each crease. In this photo, I don’t want much of the linen background fabric showing, so I’ve pulled a thread two threads out from the finished embroidery and then another at 15 threads out from the finished embroidery. Now you should have two lines of pulled threads on each side of the embroidery. Pull a final thread 7 threads out from your last crease—this will make a line for you to trim the excess fabric. Trim that fabric and get ready.
Step 2: Start by pressing in the corner to the point where your pulled threads that are closest to the finished embroidery meet. Now, press in the first hem crease.
Step 3: Press over your second hem crease. This will create a miter at the corner, but you’ll still have some excess fabric to deal with, which leads us to Step 4:
Step 4: Open out the second hem crease you’ve just pressed and trim the corner seam allowance to about one-quarter inch.
Step 5: Re-press that second hem crease back into place, and voila!, you have a beautiful mitered corner. Using good-quality hand sewing thread and a slip stitch, stitch your embroidery’s hem. Give the entire embroidery a thorough pressing on the correct setting (cotton setting for DMC floss) and then admire your lovely handwork!