Martha, my current knitting twin, wondered what the joins looked like on my shawl. I took a photo, as close as my camera will let me, and marked them
The join at Join 1 shows where I picked up stitches along the edge of the first edging.. The line of pick-ups is almost exactly under the '1' of the label. I tried a few ways of picking up the selvedge stitch, and settled on going under just one thread (not the whole selvedge stitch), since I didn't like the effect of the chain running along the backside of the shawl.
When I began binding off the middle section I discovered the chain was going to be there, whether I wanted it to or not. That join is right in a line with the J of 'Join 2'. The big holes a few stitches outside the join are the yo/k2tog in the pattern. I didn't use a marker for the first edging, but found it very helpful when working on the second half. I placed it right after the first K2 of a right side row.
And, speaking of right side rows, I discovered, very early on into knitting the second strip of edging, that in my eagerness to get to the edging, I'd forgotten the last three rows of the middle. The (fortunately) resulted in having the right sides of my edgings be on opposite sides of the shawl. I caught it (phew), frogged, cut, knit three more rows, and started the edging again.
Then I realized that I should have purled that middle row. And purled a row before starting the faggotting pattern. Oh well.
I have less than two repeats of the edging left now, and a few too many stitches left from the middle section to work together with them. A bit of mild fudging seems to be indicated.