So here's what I did, for a collarless jacket with contrast lapels. Take it with a grain of salt, because as usual I'm making it up as I go along, but hopefully this will be helpful to at least one other person!
First, assemble the lining, sleeves and all. Press the seams open, so they lie flat against one another when the jacket and lining are sewn together, but don't bother to finish them unless you're a completist like that. It should look like this:
Now, assemble the jacket itself. I always treat the lining as a sort of halfway-muslin, and use it to adjust any fit issues before I break out the fashion fabric--which, in this case, is the wool from my Dustbowl skirt, the butteriest, nicest wool I have ever fondled. I let Dottie model it:
Then, put the jacket inside the lining, right sides together, and pin the edges from one side seam to another across the front. Your back neckline, lapels, front button overlap, and front hem will be pinned; your back hem will not. Gotta leave some space to flip it inside out!
Now, sew along the edges you just pinned. It's gonna look like this:
See how the stitching starts and stops at the side seams?
Trim and clip the seams:
The sleeves are the tricky part. Note that this is much easier if you've chosen a straight-across sleeve opening, rather than the curvy one I picked. You live, you learn. Basically: notch the sleeve opening up to 1/8 inch away from the seamline, and fold under. This picture is wrong--I screwed it up the first time--you have to turn each sleeve right side out, and then fold the raw edges to the inside. Pin and press.
Now, flip the whole mess right-sides-out. Tuck the sleeve lining inside the sleeve. Press and pin with the lining rolled slightly inside the jacket. When you get to the back hem opening, tuck the seam allowance inside and pin, like this:
I had to easestitch a little bit because my lining wound up slightly bigger than my fashion fabric, but it turned out okay! Now topstitch the whole shebang--hem, front opening, lapels, back neckline--keeping the lining rolled slightly to the inside. Since my fashion fabric and my lining are very different colors, I did this with the lining upward, white thread up top and black thread in the bobbin. I didn't get a good picture of this, but you've topstitched before, you know what's up.
Now--finally!--pin the sleeve and sleeve lining together so that the rolled edge of the sleeve lining is just inside the rolled edge of the fashion fabric sleeve. Topstitch the shit out of that shit. This is how I do it:
It's kind of a pain in the ass, but you only have to do two of 'em.
I'll throw you guys some photos of the bolero itself soon--I haven't put the buttons on yet, but that's all that's left. I feel a little cranky with myself about it, actually, because there are some things I should have caught in the pattern drafting stage; for one, the shoulder point is a little too low, which makes the sleeve slightly too tight and the bodice fold over a bit at the armscye. Again: you live, you learn. Such is life.
Next up: the Dear Partner hat--I'm drafting the pattern as I type, sort of. Well, I was drafting it half an hour ago, and then I took a break. Whatever, I'm getting excited about it!