This shirt always had a weird cut and design; probably purposely, but I also never really liked the fit. When I bought it at Anime Expo last year, I originally wanted a small... when I tried to buy a small, the women at the Sexpot Revenge booth started telling me how Japanese sizes are smaller, and I should probably do a medium. Mildly offended (because I knew I needed a small, and because I own other "Japanese" smalls... I know what the size looks like), I bought the medium just to shut them up. Well, lo and behold, it was too big, and I've probably worn it less than five times in the year I've owned it. Well, it's time for AX again, so I decided I'd MAKE it wearable :) Still big, but with a bit more of a punky flair.
Fairly simple design, and probably one of my first projects without any outside help or instructions. All you need are your fabric scissors and maybe some tailor's chalk :)
I apologize in advance for any crappy pictures or instructions; my first how-to, so bear with me ^_^
First, make any cuts to the neck or hem that you want. That way you know your limits when you start cutting up the back. I cut very close around the neck seam to preserve the label on the back of the shirt, but, as you will.
Next, decide how big of a gap you want between your cuts. Obviously, the wider the gap, the smaller the cuts, the smaller your shirt stays, and the less skin or undershirt you'll be showing. My shirt had a weird cut to begin with (which could be blamed on a number of things: it was meant for cheap, mass production and overseas sales at a convention, it's Japanese and a label most often associated with punk style, I got a defunct shirt, etc.), but whatever the case, the design is about an inch off center. It's not noticeable when I'm actually wearing it, and I don't think cutting up will change it. I based my gap on the width of the label (2.5 inches) and added half an inch to either side, make the total gap about 3.5 inches.
Now, decide on how far from the collar you want your cuts to start, and then length and amount of lines. You can draw them in with tailor's chalk or what have you, but I have a habit of free cutting. If you DO decide to cut without lines, be very careful, especially if you're working with a dark shirt.
Now that you've finished the back, you can work on the sleeves a bit if you want. I cut mine above the seams, and added a few cuts. If you want to do cuts to the sleeves, just follow the same procedure as the cuts for the back. For mine, I did uneven, non-parallel cuts. If you do the same, be VERY careful so that the cuts don't actually intersect.
And then you're done :) Wear it! For a bit of color, layer it with a tank top or another t-shirt. I'll be wearing a red tank under mine to match the design on the front.