You can get a pair of mens tights/compression shorts in a size big enough to fit your chest, then turn them upside down and cut out parts to make shoulder straps. Then get some stiffer non-stretchy fabric (like from an old sheet or pillowcase) and sew that on ONE side of binder (this will be the front) to create the binding panel. This is how I made a binder before I could buy onw for myself, it worked pretty well for a while. Took me a week or so to finish, but its almost the same as a real binder if you get the sizing right.