I found this tutorial on Pinterest and decided to do my own. Here is my version:
What you'll need:
~ One Medium/Large T-shirt
Cut off the neck of the T-shirt in a large arch.
Cut off the arms of the T-shirt.
Cut down the each side of the T-shirt from arm pit to seam.
Wear the vest. You put it on by putting both your arms through the neck hole.
(It definitely doesn't look good with my sweatshirt. lol)
Here is the link to the original tutorial, courtesy of WobiSobi Blog: