Each tissue cover takes two pieces of fabric – one 6 inches by 6.5 inches and one 6 inches by 7.5 inches. The larger piece will be the inside and will form the edge along the opening.
With right sides together, pin the two six inch sides together and stitch with about a quarter inch seam. The larger piece will have a bubble. It can be stitched by hand or by machine.
Turn right side out and try to make the larger part even on both sides – this makes the edging. Give a press with an iron or you can just finger press it if you don’t have an iron.
Fold the edges to the middle and pin. You can measure if you want, but I just look at it to see that it’s even. Stitch along the sides with a quarter inch seam (I forgot to take a picture of this step).
Turn right side out and press again, if you want. Add tissues.
I usually make a bunch of these at once. I cut with the rotary cutter and stitch a string of them on the machine. Give it a try.