1a. If using just fabric just cut a piece that will be larger than you wide (I always cut a lot extra) and as long as you want it to be with a few extra inches... (I never measure anything so if you are anal about this then that would be a good thing to do)
1b. If using a pillowcase just cut the bottom part open. The bottom part that you just cut open is going to be the top of the shirt. The already sewn opening will be the bottom.
b. You will also cut one side of the pillowcase. That side will be where you put a zipper.
2. Wrap the fabric around your boobs/stomach area and pin it where you are going to want to sew (this is only a rough estimate so don't make it completely tight). Make sure the fabric is inside out and the good side is facing you body.
3. Where you have the pins take a pencil/pen and just mark the areas. Then when you take the pins out and the fabric off you can match them up roughly and re-pin it for sewing.
** When you take the fabric off if you are really curvy like me the areas won't match up completely. Then you just estimate using the mark on one side and adding or subtracting a little on the fabric.
4. Re-sew the side. To do this measure how long your zipper is and mark the end of the zipper with a pin on your fabric. Where the zipper is you are going to want to use the largest sewing gap.. Since I don't know what that is called I have included a photo.
5. Fold the top of the shirt down on the inside. This will be for when you put the elastic later and the top hem.
6. This is when you put in the zipper on the side.
**Don't sew the top of the zipper in. This will leave room for the elastic line. You will sew them all in together at the end.
7. Once done with the zipper you will start putting in the elastic. Sew a line around the top just enough for the elastic to fit.
8. If you have never used elastic before the easiest way to pull it through that I have found is hook a safety pin to one end and just push it through.
9. Once you have pulled it all the way through put the shirt, dress, etc on and see how much you want to use/how tight you want it.
10.Then pin/mark those areas on the elastic.
11. Sew those areas in at the ends with the top of the zipper. Make sure there is some a little hanging on the outside to ensure it is sewn in completely.
If it doesn't fit the way you want it to you can add darts on the sides to make it tighter in the stomach area. Just put the shirt on inside out and pin where you want to pull the shirt in. Mark the areas again and sew.
I also added the ribbon to separate the boob and stomach area. I found that it looked a lot better. To do that I just sewed the one end on by the zipper and wrapped it around so it was long enough and left extra for the bow. I haven't quite figured out a permanant way to put the ribbon on that I like. Any suggestions are welcome.
I am sorry if this is really confusing. I don't think I am very good at tutorials. If you have any questions just ask! I will try my damndest to answer them as well as possible.