Sew a piece of elastic from the string end of one teardrop to the curved bottom edge of the same teardrop.
Once you have a couple stitches in place, stretch the elastic so that the free end of elastic meets the bottom edge of the bikini top.
The starting edge of the elastic should be holding down the top seam you just created when sewing the string on.
Repeat elastic application on the other side of the teardrop, as well as both sides on the other teardrop
Flip one teardrop over so that the right side is facing up.
Hold it so that the curved bottom edge is away from you, and the string toward you.
Starting on the right side of the piece, flip the elastic under and stitch down with a zigzag.
As you come to the string end of the teardrop, flip the second (left) piece of elastic under, holding it and the first piece under so that they lay nicely.
Stitch right to the string end while holding in place, lower your needle, and pivot the teardrop so that you can continue to sew down the second edge:
Alternatively, you can sew the elastic down with the wrong side facing up. Do everything the same as described on the previous page, only upside down!