It may look intimidating, but using elastic thread to shirr is pretty easy. That way you can use a fabric that you like instead of one of the few varieties they have for shirred fabric. The ones I have seen in the store were mostly for adults, too, so the shirring was too big for a little one.
I use elastic thread all the time in making clothes for my daughter, and this is a quick and simple way to make a dress. I made this 4th of July dress in no time using the method below:
You can find elastic thread at any fabric store with a good notions supply. It can be found with the rest of the elastic, not the thread.
1. Hand wind the bobbin with the elastic thread and don't pull it.
2. Use regular thread for your top thread.
3. Set your stitch length to the longest stitch and I usually set the tension around 3-4.
4. Cut your fabric with at least a 2:1 ratio for the size you need.
5. Hem the top of the piece first. It is difficult to do when it is all bunched up.
6. Start sewing in long straight lines. You can trace your guidelines if you want or just go slowly. I use the sewing lines as a guide for distance. I go down three stitches in between each line.
7. When you are done sewing your lines, tie the two threads together. It is hard to use an anchoring stitch with the elastic thread, so tying them together is necessary.
8. Now if it didn't shirr enough while you were sewing, you can use a steam iron to bring it out. It usually shirrs more when I put the outfit in the dryer, too.