I can't find any chevron patterned fabric in the stores hear anywhere. I found some in some etsy shops but I didn't want to pay the price or shipping so I tried to make my own. Now, you can make it easier then this if you buy striped fabric, cut in strips on the bias and flip every other strip vertically and sew them all together. (if you're a good sewer and can match up all the lines).
Instead I found a chevron pattern online, printed it off then traced it onto freezer paper, painstakingly cut it out and ironed it onto my fabric (wax side down).
Then I got excited, because at the craft store I found some spray fabric paint which I thought would be easier. It wasn't. It didn't work and made a mess on my fabric which I had to cut off later.
I switched to a non-fabric plain acrylic white paint and sponge painted the whole thing.
I'm not planning on taking the pillow case off or washing it, so I hope the paint holds up.
I had to cut off two lines and I was left with just the right size to fit my pillow.
There was still a little seepage in a couple spots, but from far away it looks ok.
It's the same material I used for the lampshades.