answer:Well, my first piece of advice is to get a machine, especially since you’re clearly interested in cosplay and this isn’t a one-time issue. Search Craigslist in your area. I found my friend a basic sewing machine in good shape for $15 just last week. My first machine was from Craigslist for $30. People are always getting rid of machines on the cheap. If you do get one, find a thread that is as close in colour to the shirt as possible, get some very thin rope trim at the craft store, and sew it into the shirt, with a zipper foot, just like you would if you were making piping. Here is a piping tutorial. Instead of bias tape, just use the shirt. If getting a machine for this cosplay is really out of the question, you could, in theory, do it by hand. It would be a major pain in the arse (I personally hate hand-sewing), but it’s doable. IMO, it would be well-worth the $30 to get the machine.