@Judy> GIMP is a free image manipulation program made by users of the Free Software Foundation. It was made for Linux, but there are also Windows versions too. It's like Photoshop. You can download it at
http://www.gimp.org. Photoshop users use it pretty easily, but if you are not familiar with this kind of photo editing, there IS a learning curve.
@Jo>I prop the form on a chair. I have a female molded torso that I can hang for dresses. But it takes small dresses. I do it in my living room with the shades drawn and the light directed at the floor.
All the shirts I photograph are small or medium. The big ones just 'hang' on the forms. For big shirts I hang them on a piece of PVC pipe.

I should have let the wrinkles hang out before photographing it. My bad.
Here's one with the sleeves pulled out straight. This photo was taken in my store, and the window is to the far left in relation to where the shirt was hanging. Also I didn't have the camera directly in front of the subject. That is why one sleeve looks smaller than the other.

The torsos are great. They are cheap, light and really go a long way in selling the item. I take six to markets with me, nested within each other with the clothing still on them.