Lay out your main fabric (MF) and lining, wrong sides together.
Then sew a basting stitch (also will be your gathering stitch) along the bottom and curved top of the sleeves. You can pin if you want, but I like to live on the edge!
I also cut out two strips of my MF, 2″ x 9″. (you can measure around your child’s arm and add seam allowance for the length. I add a bit more so it’s not tight around her arm)
(not shown) Then iron in half lengthwise.
So here’s the sleeve sewn together with the gathering stitch.
Start pulling one of the threads on the bottom to gather…then pin the strip you ironed in half to either end, and fit the gathers to the strip. (raw edge of the strip towards the gathers)
This is what it’ll look like now, pinned together.
(not shown) sew along the sleeve bottom
and finish the edge with a serger or zig zag stitch if you like. (not entirely necessary, since I folded it over and sewed it down again, you’ll see..)
Next gather the sleeve top to fit the arm hole and pin it right sides together.
You can do this before sewing it into the armhole, but it’s just as easy after also. I then folded over the strip and pinned it around the edge.
This is how it looks from the front. You could hand stitch this down, or…
Just stitch along the edge like so.
Next, pin the bodice right sides together, and sew the side seams together, then finish the seams with serger or zig zag stitch!
Pardon the pic from another dress tutorial!