I took this adult men's small t-shirt and made it into a fitted women's medium with a boat neck. Supplies you will need other than a shirt you'd like to downsize are a fitted t-shirt to use as a pattern, pins, an iron and a sewing machine. I used thread that matched the color of my shirt but you can use any color. If you mess up and make the sides too small you could always sew in some fishnet material or other material as a spacer in between the seams. I know girls that used to just pin up the sides with safety pins anyway. There are no real mistakes with this project. I tried to make the instructions easy but if you have any questions let me know.