Trim the fabric into thirds to create long strips. For me, each strip was 15″ wide (for no other reason than what my fabric width allowed). Two strips will run the length of the bed, wrapping around the back, while the third was cut to the width of the bed to run along the front panel (5′ for me, my bed is a queen).
Sew all three together at the short ends to create a long fabric band, and then pull a Hercules and hoist your mattress against the wall. Just for a minute. Put the long fabric band in place around the bed, just to make sure your seams hit right at the front two corners for that “completed” look. I tucked mine under and let them drape over too, just to see how much overhang I’d have in width. Theoretically, at this point you could pull your still-fully-dressed mattress back down onto the box spring and call it a day; the mattress would hold it in place. But I took it a few steps further to create a really finished look.
I took a close look at each of the corners of the bed. With the overhang that fell on top of and below the box spring, I proceeded to hem the corners in the same way I would wrap a birthday gift.
I sewed each corner in place so that the box spring band would wrap securely in place the same way a fitted sheet would.
When all four corners were completed, it was already showing signs of polish.
Make the wrap fit really snug; cutting one yard of 1-1/4″ sports elastic in half, I attached it to the part of the wrap that remains hidden behind the head of the bed, against the wall. Yes, it stretched enough to span that 30″ gap between the ends of my fabric.
Like the elastic on a fitted bed sheet, it gives a little stretch to allow you to slip the box spring cover on (and off, when you want to wash it if your dog snuggles against your bed like mine does). Easy.
The corners should fit securely, the elastic should keep it from popping off, and your bed should look all fresh and clean (so clean, clean). See what I mean about it almost looking like you have an actual platform bed now? If you didn’t know I had just covered the box spring would you guess that there was no real bed frame?