In this tutorial, we learn how to change a t-shirt into a sexy one piece. First, lay the shirt flat on the ground and then use chalk to trace where you want the new one piece to be. Next, cut on the outside of where you made the marks. After this, use pins to keep the sides together, then sew the sides together so it makes one complete shirt. After this, cut strips of fabric out and sew them onto the top of the shirt where the straps are going to go, then on the sides. When finished, put it on and you will have a really cute one piece!