So I got this free t-shirt in the Chicago airport. I never wear t-shirts. What's more, this one was an extra-large men's (I wear a women's small), and it had a lovely graphic of Chicago on it.. but I've never been outside the airport, so I'd feel like a poser wearing it.

I decided to take this gigantic hunk of fabric and turn it into a shirt that I might actually wear.
In short, I wanted to make it unrecognizable.
I think I did.

This garment has two cinched sections (on the back/sides), a corset back, a sweetheart neckline, and rouched shoulders and front.

Step 1: Materials

Your giant t-shirt
Scissors
Needle
Thread

Step 2: Cut Some Bits Off

Cut out the collar and any graphics you don't want. In my case, I took out the whole Chicago graphic and the little logo below the neck at the back. Since the graphics part left a hole in front of my chest, I flipped the shirt around. The front is now the back, and it's modest once again.

Cut off the sleeves.
Cut off the bottom hem.

That means the only original stitches left in this garment are the shoulder seams (and maybe side seams, if your shirt has those). You have a giant tank-top with a ridiculous neckline.

Even out that neckline so that, even though it's huge, it's a smooth edge; remove any weird pointy parts left over from cutting out graphics.

Step 3: Make the Sides Cinched

Lay your shirt out flat. We'll be sewing on the right sides of the shirt throughout this instructable.
On both sides of the shirt, measure in two inches and mark a line. Sew a straight seam up the line.

Press the tube you've made open. Press it down in the middle, and sew straight up, turning your one tube into two adjacent tubes.
Repeat on the other side.

Remember that hemline you cut off of your shirt? Snip it open at both sides. This is your drawstring for the two sides. From the bottom of the shirt, feed the cord up through one of the tubes, then back down the other one. Choose your desired level of cinch, then tie at the bottom. (For a more finished look, sew across the cords and tuck the ends back up into the tubes.)

Step 4: Roucheing Front and Shoulders

Make large stitches straight down the center front of the shirt. Pull to create small gathers. In smaller stitches, sew over it again to lock gathers.

Repeat this process on the front of the shoulders. This should create the sweetheart neckline effect.

Step 5: Corset Back

Return to the cinched sides. With your scissors, poke small holes through the side. Poke in pairs, as shown. I did four pairs of holes on each side.

Cut off some rings of sleeves, cut open and sew together to make more cord.

Thread corset strings out through the top holes, then back through the second holes. Cross and repeat.
Tuck the ends through the tied loops at the bottoms of the cinches.

Step 6: Finishing Touches

Cut the back down the middle and (right sides together this time) sew together as tight and as high as you want it.

Alternately, don't sew together and tuck the flaps away for the punkier look pictured above.

Cut off the bottom in a half circle to avoid the 'bum roll' look.