Since nothing was exactly like what I wanted, I did a mash-up of THIS YouTube video, the written instructions, and my own ideas on what I wanted the edging to look like.
After reading through the project pages for the pattern, it seemed like a few people struggled with this technique, so I decided a photo tutorial might be helpful as well. My technique is not the same as what was in the pattern, but I think the end result looks nice.
I hope these photos are helpful to some of you as well!
Let's get started!
There is a lot of knitting stitches onto the right-hand needle and then transferring them back to the left-hand needle. It's fiddly, but it works.
It's helpful if you read through all the steps and look at all the photos at least once before you attempt to knit at the same time. It may not make sense while reading it, but once you start knitting, it should become clearer.
1. First, slip all of the required stitches onto your designated circular needle.
(You will only need 1 circular needle to do this technique.)
2. Cast on the number of stitches instructed in the pattern onto the right-hand needle of the circular needle.
(In the above picture, the needle resting in the middle of the sweater is the right-hand needle.)
(In my case, I needed to cast on 2 sts.)
3. Move the cast on stitches from the right-hand needle onto the left-hand needle.
4. Knit the first stitch on the left-hand needle.
5. Slip the 2nd stitch as if to knit.
(You now have 2 stitches on the right-hand needle.)
6. Slip the 3rd stitch (which would be a picked up edge stitch) as if to purl.
7. There are now 3 sts on the right-hand needle. (One knit stitch and 2 slipped stitches.)
8. Move the 2 slipped stitches back to the left-hand needle and knit them together through the back loop (you have now done a SSK).
9. You now have 2 completed stitches on your right-hand needle.
10. Move these 2 completed stitches back to the left-hand needle. Wash, rinse, repeat. (In other words, you do steps 4-10 over and over again, until you either 1) reach a buttonhole or 2) have gone all the way around your project and are ready to bind off.) Your next step here would be step 4, knit the first stitch.
Applied I-Cord for Buttonholes
1. In my project, the cardigan calls for buttonholes along the applied i-cord. To prepare for this, when picking up stitches, I skipped picking up one stitch because this is where the buttonhole would be placed. At this point, you have done steps 4-10 of above until you reach your skipped stitch. Do you see the 2 garter ridge bumps in the photo below? Between those bumps is my skipped stitch.
2. Now that you've identified buttonhole placement, place the two sts from the right-hand needle onto the left-hand needle. (You've done this much lots of times before...just stick with me for a moment.)
3. Now, instead of knitting the first stitch and slipping the 2nd stitch, you are going to knit 2 sts. (So the 2 sts you just placed back on the left-hand needle will both be knit. Do NOT knit them together, just k2.)
4. Here are your two knit stitches on your right-hand needle.
5. Slip the two knit stitches back to the left-hand needle and continue as from the top with steps 4-10 (knit 1 st, slip 1 knitwise, slip 1 purlwise, k2tog tbl).
6. Do you see what this does at the buttonhole? You have knit a portion of your i-cord as you would any normal i-cord, leaving a gap for the buttonhole, and kept your knitting from puckering. Do you see my buttonhole in the photo below?
7. From this point, you continue this technique over and over. My pattern called for buttonholes every 4th stitch, so I have a total of 7 buttonholes. Your item may not have any buttonholes. Keep up the k1, s1 knitwise, s1 purlwise, k2tog tbl - move back to left-hand needle. When you reach the end, bind off as you normally would any i-cord. In the above linked video the woman uses an invisible cast-on and then does a kitchner or 3-needle bind-off to pull it all together since she's going around a blanket edge.
I hope this was helpful. It still feels clumsy and complicated to me in just written and photographed form, so I plan to try getting a video tutorial added to this as well. Until then, feel free to contact me with any questions you may have regarding the tutorial and I'll do what I can to help.