Disclaimer: Please pardon my yoga pants and bare feet. It's late.
I followed the instructions, folding the fabric in half, measuring 6" down and over and cutting an 8" armhole. This wasn't long enough for me so I cut 3" more. (This photo is sideways, the fold is at the top)
I love how oversized and flowy this is, but realistically I would not be able to wear this to work (where I spend 90% of my life), so I decided to alter it a little bit, hoping I could keep the flowy awesomeness.
I used the excess I trimmed from the bottom to bind the armholes, leaving both the outside and inside seam allowances raw. This will keep them from stretching out of shape but still keep the simplcity of the fly-away vest.
Love the result!
Defnitely check out the original tutorial here and let me know if you've tried it too!