Butterick 5678 here. I'll warn you now, there are quite a few posts.
The instructions for this sleeve are on the Sew News blog and you can find them here, http://www.sewnews.com/blogs/sewing/2014/07/17/sew-along-extra-summer-breeze-top-adding-sleeves/
You may have noticed that the hem of this blouse has a little extra fullness. I added a little something extra for anyone who might have mis-measured and the hip area of their top is just a little snug. It will be in the final sew along post this upcoming Monday.