Making Straps for a Strapless Gown or Dress Using the Hanging Straps

We found a bunch of new dresses at a second hand store about a year ago. Princess Five picked out four dresses she could wear to different dances at the school. They were between $15 and $20 each but still had the original tags on them. Some were samples and others were maybe overstock and others still needed mending somewhere. 
 
The dress she wants to wear to prom is a light green dress. It didn't come with any straps but has the snaps and hooks for straps. Matching the color of green of the dress would be extremely difficult as I tried not only at our local stores but those in the major cities near us. 

The dress is a bit large and needs to be taken in at the sides. Here is a link to me altering another of the dresses we bought that day for her to wear to Winter Ball a few months back.  Here is a link to what the finished dress looked like on her date to the ball. 

This dress only needed to be taken in about an inch on the top of the dress tapered to the waist so it was easy. In doing that, I realized that I needed to remove the straps that are on the inside to hang the dress on the hanger. They are the same color as the dress which isn't always the case. 
 
I was able to take them out of the inside lining seam and then just loop them through the thread "hook" catch near the plastic snaps. I stitched the front ones on the sewing machine making sure the stitching didn't show.

I then tried the dress on her and was able to pin the straps to the right length on the back snap / hook area and then stitch it once it was off using the machine. 

Even though she doesn't want to wear the dress without a jacket, she wanted straps so she didn't feel like she needed to pull the dress up all night. 
 
Even if you needed to use a different color fabric for the straps, you could then bring that same color in by making a belt or sash of the same color or a "rosette" of the same type fabric for her hair or something to tie the color in some how. 
 
I am working on a jacket at the moment and hopefully can get it finished soon as we want to start working on her hair style. We tried a loose one today but want to try a few others before the dance to make sure she has the hair style that is just what she wants to feel like the Princess she is.