To finish the blouse, I just needed to set the sleeves, do buttonholes, and finally buttons. To space the button holes I cheated by laying another blouse on top and copying the placement. Easy schmeasy.
In order to do buttonholes, I have to pull out my vintage buttonhole attachment. It sometimes gives me difficulty because I don't have the correct feed dog cover plate for my machine model. As a work around I lift the feed dog plate with a lever on my machine. It works ok, but isn't ideal.
Pencil may not be the best marking method, but it got the job done and it isn't visible on the final shirt.
Finally, I stitched the buttons on with my button tacker foot. I marked the button placement with pins, which are removed once I start stitching.