After I serged finished all edges of the fabric and began the sewing process for the Emma top, I pulled out some lightweight, gimp thread I have had forever. I used this mostly to give buttonholes some body when necessary. This is perfect thread for use on a lightweight fabric like the one am using for this top.
First you lay the gimp within the seam allowance under the presser foot.
I used this method on a heavy wool skirt and I used a piece of knitting yarn to do what the gimp does for lightweight fabric. After all pieces are attached as the pattern calls for, you can then remove the gimp. For this top, I cut off the tails and left the gimp as it gave the gathers a little more body.