I'm sure it's not the first time it's ever been done, and it probably isn't as creative as I thought I was being....but I am pretty proud of how this whole thing turned out!
(keep in mind I am no seamstress or tailor, so this is not very "professional" or precise)
What you will need:
* sweater/shirt of your choice (knit is preferable because it doesn't unravel as much as a woven)
* sewing machine, serger, OR needle, and thread matching your sweater
* ribbon/lace/trimming for the finish (optional)
I used a zig zag stitch all along the edge of both cut sides. You can take it one step further and hem the edge, for a nicer finish. I skipped this step because (if you look close) the edges sort of rolled in on itself, so I didn't feel that it was really necessary.
You can take it even another step further and go for a cleaner finish, by using a ribbon or some lace. This can also add some flare to your new cardi (example below). I kept it simple this time, but I am loving all the different options and possibilities! Also, to have it close in the middle, consider adding loops/buttons or hook/eye.
Now go through your closet and find that sweater that's been collecting dust, and make it a staple in your wardrobe again!