|A picture of the top lying flat is here - http://bp2.blogger.com/_e2XwlkD5wb0/RpSGzxjpi7I/AAAAAAAAAgk/jUR7LNQD4vw/s1600-h/DSCN2671.JPG.
As you see, it's a piece of organza ribbon, embellished with one of my machine's decorative stitches and sewn to the bustline of a knit top. Now, there is a problem, the top does stretch (quite a lot) and the ribbon not at all. So how did I do it?
First, I decided to put the ribbon only on the front of the top. I guess I could have put it on the entire circumference, but decided that I would like it better to still have the entire stretch in the top back. That way, if I did a mistake and sewn the tape too tight I would have still had plenty of stretch in the back to pull the top over my head.
I measured carefully my underbust line, wearing a fitted T-shirt (so I could see the side seams and know where to stop), cut a piece of ribbon of the respective length plus seam allowances. Embellished the ribbon, see here how I do it - http://sewing.patternreview.com/cgi-bin/review/readreview.pl?readreview=1&ID=1500.
I then quartered the ribbon and the underbust seamline on the top (after assembling the upper front and the lower front bodice and pressing that seam). Matched the ribbon and the bodice - you'll get a lot of ripples in the ribbon, but don't worry, it's normal. You can pin the ribbon to the bodice, but as I treated the ribbon with steam a seam before embellishing it, I was able to fuse it on the bodice (while stretching the knit to match the marks on the ribbon).
I then sewed the ribbon on the top, using a stretch stitch (zigzag 1 mm wide and 2.5 mm long).