For a 17" pillow you'll need 28" of fabric (by the width probably 44" or 60").
For a 17" pillow case you'll need fabric cut to 17x38 (pillow case), 9-11x38 (bow), 6x6 (bow tie). My red pillow case I used the 11x38 inch bow and the pink one was a 9x 38 inch bow.
Stare at it and say, that was so easy and quick and look how cute my pillow case is.
I hope you like it. I posted this originally on my blog http://raegunwear.blogspot.com
I'm brand new to instructables. If you have any questions please let me know I'll do my best to remember to check in but you may get a quicker response if you post the question in my comments section on my blog post for this tutorial or send me a message.