I am not very good at sewing. I make things that I don't have to follow patterns! These pillow covers really were very easy. I was pretty much winging it and that is just how I sew because I am not good at math. Sorry ahead of time for the lack of measurement numbers! Just measure the size of your pillow and add an inch to the length and width. When I bought my fabric I had them cut the perfect length and then the fabric was just about the right size to fold over the pillow with a little extra for the opening. Sew a hem on each of the short sides.
Fold the length right sides together almost in 3rds. Pin and sew 1/4 on each open side.
Turn right side out and sew 1/4 hem all the way around if you want to. I didn't but it would reinforce the seams. I really couldn't fit it as most of them came out a little small (I am not very good at measuring either it seems!) and I was trying to knock out 6 pillows in one naptime! It took a little longer but not much.
Stuff your pillow in the open flap and viola! A pillow cover! I was so happy to cover the pillows that came with our couch. They were just dark and too matchy for me. Keep in mind that the pillows may be stuffed with different amounts of stuffing so they may be different sizes.....this happened to me and some of my covers were very very snug! Oh well, next time I will measure each of them.