I promised I would post how I made the sleeves for THIS post.
I started off with a rectangular piece of fabric that will be the straps. You can make the strap as wide or thin as you would like. To figure out the length, I had my daughter put on the top (minus straps) and measured over the shoulder front to back. I added an inch to both ends to be used when attaching it to the bodice.
Next I cut the sleeve to be attached to the strap. I freehand cut it. You can draw the shape onto a piece of paper for a pattern if that would be more comfortable. I cut it while folded in half so both sides of the sleeve would be the same. Make sure to cut two sleeves, using your first as a pattern for the second.
Here it is laying next to the strap fabric to give you an idea of the proportion.
Next I serged the curved edge, folded it over, ironed and sewed it down. If you don't have a serger you can fold over the edge twice and sew.
Now I sewed a seam down the inside straight edge to make a gather. Do not back stitch and use the longest stitch your machine will allow.
Then pull on the bobbin (bottom) thread to create gathers. I kept my gathers in the middle.
Next I lined up the gathered edge with one side of the strap. I pinned them together in the middle.
Then I pulled over the other side, creating a sandwich with the gathered sleeve in the middle. The right sides of the strap will be facing each other. I pinned the sandwich together from he middle out.
I sewed a 3/8 seam down the side.
Then I pulled the strap right side out and ironed it flat.
That's it. It's already to be attached to your top.
Let me know if you have any questions.