I managed to salvage it by adding ribbon around the waistline where I horribly mangled the gathering of the fabric. Well, actually I managed to do the gathering part okay; it was the sewing of the gathering part that gave me problems. The shirt kept bunching up while I was sewing and I didn't realize it until it was too late.
Here is what I learned from this project:
1. Sew very SLOWLY and CAREFULLY when you are sewing the gathered fabric to your shirt.
2. If you use the sew-two-lines-of-stitching gathering technique - after you sew it to the shirt, you can remove those two lines of stitching so that you don't see it on the front. (My SIL told me this after I had already butchered it!)
3. If you've never sewn gathers before, you might want to practice first on an old shirt and scrap fabric.
As you can see in the photo above, I have another one of these to make. Here's hoping the next one comes out better!