Once you have gone back through and are back at the point of having an outlined and fully quilted and stiffened pattern piece on a block of fabric, it’s time to line. Iron out and lightly starch your lining fabric.
Flip your pattern pieces over on the lining fabric so the drawing is facing downward to the lining.
Clip the lining to the block around the edges, making sure to keep the lining taut. Use clips as pins will struggle to get through that many layers of stiffened fabric.
Set your machine to a short and narrow zig-zag. On my machine, the default is 3.5 by 4; I adjust it down to 2.5 by 2. Using the straight stitch outline as a guide, sew the lining to the quilted layers around the edge, just to the INSIDE of the stitched outline. This helps avoid fraying of the lining at the edges.
Now flip the pattern pieces over and cut them out of the blocks, between the zig-zag, and the drawing line. This gives you an exact replication of your pattern piece.
Now we answer the question of why the pattern does not include seam allowances.
We just don’t need them.
Press out your face fabric, if you can. Linen in particular needs to be ironed out before using it as a bodice because it relaxes and stretches out with heat. If you don’t preheat and stretch it, it will relax due to your body heat and cause wrinkles on the bodice.
Lay out your pattern pieces , lining side up, facing you, and cut a block of your gown fabric. Leave a minimum of two fingers width all the way around.
I start with the vertical edges–the side seams.
On one side, pull the fabric up over the edge gently and clip it in place. On the opposing side, pull the fabric up over the edge securely, fold the raw edge under, and clip in place all along that edge. I usually split the amount I have to work with, so that the raw edge of my facing fabric lines up on the inside with the raw edge of the pattern piece.
On sections that curve quite a bit, you will likely need to trim down the amount of excess you are dealing with, and possibly clip into the edge to ease it around the curve. This means that the armhole and neck edges are narrower than the side seams and waistline. When using delicate fabrics, I often make a bias strip out of scrap and apply that to the inside edge over the actual edge to protect it.
It helps to trim down and miter corners. It reduces bulk along the edges and keeps your corners, especially on straps, exactly where they should be.
For corners, first finger press the already folded edge so you can clearly see where the lines are. Trim out the section of the fold that is hidden from view, and about half of the allowance you can see. Now when you fold the completed edge over to the side you’re working on, it has 2 layers of fabric, not three.
When you fold the new edge upwards, the line at the corner will be at a slant, away from the actual corner.