I made a simple knotted tee using this plain gray t-shirt I had. I cut the neckline of the shirt into a bigger roundneck and cut the shirt all the way down on the middle-left of the shirt. Then I knotted the top part of the two sides and sewed the knotted part from the inside. (I tucked the knotted part inside the shirt.) *note: when knotting, it's more like twisting one side around and under the other side while the other side doesn't really move except just bunching it up.) and after... I wouldn't recommend using an already tight shirt to do this project since you cut the middle and sew it back up. My t-shirt was a size medium. my project took me about 10 mins. and it cost me nothing!