How to Make a Large Cushion

Measuring for Your Cushion

• 1

  Lay out your foam and decide what shape your cushion will be. A square or rectangle is simplest to cut. Circles and other shapes require more skill. Mark the lines of your cut on the foam with a marker, and cut with the electric carving knife for a straight cut.

• 2

  If you need to join two pieces of foam together to make one large cushion, use hot glue.

• 3

  Measure the length and width of the surface of your foam. Add the measurement of the thickness. For example, if your piece of foam measures 36 inches by 36 inches and it's 4 inches thick, then your measurement will be 40 inches by 40 inches to account for the sides of the foam. Add 2 inches to account for bulk and seam allowances. Therefore, your final measurement will be 42 inches by 42 inches.

• 4

  Cut two pieces of your plain fabric according to your measurements from step 3. This is for your pillow insert. This plain fabric can be a broadcloth, a muslin fabric, or even a white sheet. Sew together three of its four sides, leaving one side open to insert the foam. Turn inside out.

• 5

  For a sharp-edge look, use only the high density foam. For a more fluffy feel and extra softness, wrap your high density foam in two layers of batting. Cut the batting to wrap around the foam cushion. Hot glue it in place. Add another layer of batting for more thickness.

Making Your Large Cushion

• 6

  Take your cushion insert cover and insert your foam, or foam with batting glued around it, inside. Pin the opening closed with straight pins, and sew closed with a hand needle and thread.

• 7

  Double check the measurements of your pillow insert now. You should still be able to use the original measurements from step 3, but depending on the thickness of your batting you may need to add an extra inch or two to all sides. Cut two pieces of your decorator fabric using your specific measurements.

• 8

  Sew the two pieces of decorator fabric together with right sides facing each other. Leave most of one side open, sewing past both corners on this opened side by about 5 to 6 inches.

• 9

  Open the fabric at each corner and form a triangle fold perpendicular to the seams. If your foam is 4 inches wide, sew a seam at the base of the triangle that is 4 inches long. If your foam is 5 inches thick, sew a 5-inch seam across the triangle's base. This seam will square each corner once the fabric is turned to the right side. Cut away the excess fabric and turn the cushion cover inside out.

• 10

  Insert your cushion insert into your decorator cushion cover. Maneuver the foam to fit evenly into each corner and smooth the fabric over the insert.

• 11

  Pin the cover's opening closed, and hand sew with a needle and thread. Snip away the excess thread.