I begin with the main body of the gown in three pieces rather than a separate skirt/bodice that are then sewn together.  As it will be covered by trim, the shoulder seams are on the outside.  Pinned to the front is the inset, which will be sewn momentarily.  The fabric is a bit stretchy, so will pull over the head rather than need to be zipped.

Next the lower, full part of the sleeves are sewn to the upper arm pieces just above the elbow.  I was on a roll and didn't think about taking a photo at this point.  After that, they are set into the main body of the gown.  Both sleeves are on in this picture, but only one is held up by a doorknob.  I didn't want to put a nail in the wall to get a picture of the other sleeve up as well.

I prefer to trim the neckline first.  I begin by sewing the sequined, beaded trim's edge to the edge of the neckline, wrong-sides together, edge to edge.  Trim for this standard version might vary, depending on availability.

Then I fold it down and sew the other edge.  This results in the seam allowance being hidden and eliminates the risk of the seam popping up. 

With the sleeves, I simply hand-sewn the top and bottom edges to the upper arm part of the sleeve.

Next, a thousand or so gold-plated beads are individually hand-sewn along the top and bottom edges of the sleeve and neckline trim, as well as around the wine-colored "inset."  This is my favorite part.  I counted 438 beads between the two sleeves and 543 for the neckline.  The photo on the top left shows only the sleeves beaded, and the photo on the top right is with beadwork completed. 

Finally, 11 buttons are sewn down the front with the 12th sewn to an inner seam in case one comes loose.  The buttons are sold on cards of three, so if I have to buy 12, may as well include the last one as a replacement.  This close-up of the 12th button, sewn to the left seam at about knee-height, shows the buttons used.