- Gather your tools. You need to prepare a pair of scissors, tape measure or yard stick, needle, thread, and sewing machine. Hand sewing is generally not recommended for this project, especially if you are using an upholstery fabric.
- Measure your window seat. Using a tape measure or yard stick, take the width and length of the window seat. The measurements of the window seat are also the measurements of the fabric.
- Buy the fabric. Especially if you intend to use the window seat often, your upholstery fabric should be sturdy. Otherwise, you may need to replace your fabric every after few months. Also, pay attention to the fabric color and design. Your window cushion should foremost complement the theme of your house or at least blend with the color of the nearest sofa.
- Prepare the foam. You don’t necessarily have to buy new foam. Old foam or foam chips from an old sofa or mattress can make a good cushion. But should there be a need to buy, choose the one that is comfortable and durable. There are many types of foam available today. You can have, for instance, memory foam or futon. Once you have the foam, cut it following the size and shape of the window seat.
- Assemble the cushion. First, cut the fabric according to the measurements of the window seat. Just add half an inch for the seams. Then, after turning the fabric right side in, sew the three sides of the cushion. Make sure the stitches are consistent and sturdy. Turn the cover right side out, and slip the foam into the open end. After which, sew this end close. If, however, you need to make a replaceable cover, you can sew a zipper on the open end of the cover.
- Test the cushion. Fit the new cushion into the window seat. Make sure the foam is well distributed across the entire cushion. Also, check that the window seat cushion does not slip off the seat. If it does, you can use a tape to keep the cushion firmly in place.
You may want to repaint your window seat to complement your new window seat cushion. Just make sure to remove the cushion or cover it with newspaper to avoid staining it. You can also make the window seat cushion even more appealing by sewing pillow cases from the same fabric. You can of course purchase throw pillows if you prefer, only ensure that the throw pillows match the color of the window seat cushion.
