Shawl pattern help

Hello!

I am knitting the Drom (Dream) Shawl from Raverly. It's very nice and simple, well at least I thought it was simple enough. For the first 200 some odd stitches the pattern states to do garter stitch. Okay easy enough, I hate the look of garter stitch so I switched that over to be stockinette stitch. This part I'm good with. The part that I'm having issues with is the edging.

This is what the pattern states:

Begin edging by casting on 16 sts at end of the row. (OKay I'm smart. I understand this. Knit the first 3 stitches before the marker and then cast on 16 more stitchesWHAHAT!?)

Row 1(WS) k15, ssk; turn. (Turn? Why turn? what about the rest of the row?) The edge has 16 sts and the shawl stitch count has decreased by 1.

Row 2(Rs): k16; turn. (Still what about the rest of the row? AND what about the other end of the shawl?)

Then it wants me to repeat these two rows twice more.

What am I doing here? Am I adding 16 stitches by casting on 16 more and then knitting across them and across what I already have on my needles? But then what about the other end? It doesn't state to put the other half of the shawl onto waste yarn so I'm assuming that I should work across everything, but then won't it be uneven? And the shawl is even, it's not one of those uneven looking shawls that I've seen online. Or am I supposed to add 16 stitches at the other end when I get there? I'm so confused.

After that it goes into the lace pattern for the rest of the edge, 12 rows of lace/cable work. And don't get me started on the lace work. The pattern/chart seems easy enough. I had to write it all out because I can't read charts very well without doing the even rows backwards, but that's besides the point. But it then says to rep row 1-12 TWENTY TWO TIMES! like! WHAAT? Am I supposed to go through the whole set or 12, 22 times or am I supposed to go though it just once more resulting in 22 rows?

It's a free pattern on Raverly and here is the link if someone needs to read it over. THis is my second shawl and I just wanted to have something in my hands to keep my mind off of my upcoming wedding. Please someone take pity on me again. https://www.ravelry.com/patterns/library/drom---shawl