For the longest time I have had a piece of extra upholstery fabric from when we created our headboard, over a year ago. (See that here: Pinterest Home Improvement: Headboards) I finally decided that I would cover 2 of the 4 of my old sofa pillows, ones that came with the sofa.
This project took me 1/2 hour to make and $0 dollars, since I used fabric that I already had from my headboard project.
I usually get my fabric from Zimman's in Lynn, MA, but, Amazon has some fun upholstery fabric for sale.
After measuring the pillow and fabric here are the steps that I took to finish the pillow cover.