Throw pillows are an easy and inexpensive way to add punches of colour to a room with otherwise neutral decor. Envelope cushion covers are a convenient way to cover pillow forms because they can easily be slipped on and off a cushion for washing or if you decide you want to change the cover on a form. Make your own envelope cushion covers with just a few folds and straight stitches to a piece of fabric.
Measure the height and width of your pillow form. Pillow forms are plain throw pillows and can be found at fabric stores.
Cut a piece of fabric that is 1 inch taller than the height of your pillow form and 6 1/2 inches wider than twice the height of your pillow form. So, for a 12-inch square pillow form you will cut a piece of fabric that is 13 inches tall and 30 1/2 inches wide.
Fold over your fabric 1/4 of an inch toward the wrong side of the fabric on both of the shorter edges of your fabric. Press this fold.
Fold the short ends over another 1/4 of an inch and press this fold as well.
Sew along the very inside edge of the folded ends of the fabric to hold the folds down and create a nice clean edge.
Lay the fabric on your work surface horizontally with the right side of the fabric facing up. Lay your measuring tape along the top edge of the fabric.
Fold the two short edges of the fabric in toward the middle of the strip until the width of the piece is the width of your pillow form. The ends will overlap by approximately 3 inches.
Pin the fabric in place along the top and bottom edges to hold it in place while you sew.
Sew along the top and bottom 1/2 an inch in from the edge.
Remove the pins from the pillow case.
Turn the pillow case right side out through the opening in the middle, where the two short ends overlap. This is also where you will stuff your pillow into the envelope case.