I purchased some complimentary material from Spotlight (the retro cat print is for the pressie, but just so happened to fit into the colour scheme I was going for!). I always pre-wash my material to allow for colour fastness and shrinkage. Once washed and pressed, cut your material into three pieces. I have chosen to make my cushions 45cm x 45cm including the 1.5cm seam allowance.
Cut one square of 45cm x 45cm and two pieces of 45cm x 32cm that will make up the overlapping "envelope" at the back of the cushion. I have allowed for a 15cm overlap, plus a 2cm hem for the opening of the envelope.
Press and hem one long edge for each of your 32cm pieces, making a 2cm seam allowance.
Right sides together, place one of your 32cm pieces on the larger square with the hemmed edge facing the centre.
Right sides together, place the second 32cm piece on top of the other two pieces, again with the hemmed edge facing the centre.
Sew around the entire perimeter of the square. I like to back stitch at the start and end of my sewing, as well as where the material overlaps for the envelope pocket. This just adds to the strength of the envelope fold when you are inserting the cushion insert.
Trim the corners off each edge of square to eliminate the bulk when the cover is turned inside-out.
Turn out your covers and press. I like to use the non-pointy end of a knitting needle to really get those corners out. Remember not to push too hard though, you don't want to make a hole in your completed handy-work!
Insert your cushion covers and stand back to admire a job well done. How easy was that! Just a little tip to make your cushions look extra plump and comfy... always get an insert that is slightly larger than your cover. You don't want your insert swimming around in there.
For a more festive look, why not grab some Christmas material and whip yourself up some holiday cushions - the sky's the limit.