Lesson Three: Knitting in the Round
I hate to admit it, but not everything about knitting is fun. I love the process of knitting, making knits and purls and seeing a project progress from a single strand of yarn into a beautiful piece of fabric. But I hate — hate — having to do a lot of finishing. If I have to do more than weave in a couple of ends, I'm ever so cross. Some projects absolutely require sewing pieces together and seaming and the like for structural stability, but I still don't like it. If, however, I land upon a project knit in the round? Oh, boy, am I happy?
Knitting in the round is simply knitting a tube rather than back-and-forth. You're always working on the right side of your project, too, which means that stockinette is super easy (regular back-and-forth stockinette is knit a row, purl a row; in the round, it's all knitting). And, best of all, there's so much less finishing to do!
There are several ways to work in the round: double pointed needles (DPNs), circular needles of an appropriate length, two circular needles at once, the magic loop, or even double knitting. Most patterns will suggest a method, but you can always adjust it if it's not your favorite. But they all work on the principle of knitting the first stitch cast on directly after knitting the last stitch cast on.
I should note that I'm quite comfortable with DPNs, circular needles, and two circular (or "circs") needles at once. I have not tried the magic loop and can't give much more help than a basic idea of the theory behind it. If you want to read more about it, I would suggest starting with this tutorial on weebleknits.net.
Knitting in the round
To knit in the round, cast on your stitches and, if necessary, distribute them over your needles. Make sure the cast on edge is not twisted around itself; when the needles are laid down, the cast on stitches should all be on the same side of the needle. Personally, I find it easiest to arrange the cast-on edge so that it's around the inside of the needle circle. (I'm sure that makes no sense without a visual aid, which will be coming in due time, I promise.) Now, bring the beginning and end of your cast on edge together and join them by working into the first cast on stitch. Work across the row until you get to the last stitch.
Stitch Markers
When working in the round, it's important to know what your first stitch is, as this is where each row starts. When working with DPNs or two circs, this is pretty easy, but when you're working on an appropriately-sized circular needle, you're going to need a stitch marker. Stitch markers can be any number of things. You can buy gorgeous custom designs or generic, mass-produced ones; they can be complete circles or they can be split for easy removal. You can even use a soda can tab. (Yes, I've done that. It was kind of fun, in a reduce-reuse-recycle sort of way.) But, by far the most simple and easiest to obtain stitch marker is a scrap of yarn that you tie into a loop.
Typically, you place your stitch marker on your needle between the last and first stitches. There it sits as you work your way around your work. Then, when you reach it again, simply transfer the marker from the left to the right needle and continue knitting. This way, you'll always know where your first stitch is.
Stitch markers are also useful when you're working on big projects. You can use them to mark any sort of thing in your knitting that needs marked. You can place them between pattern repetitions or where you need to increase or decrease or whatever else seems useful to you. Don't be afraid to experiment.
Double knitting
Not having much experience with double knitting beyond swatches, I can't say much about it that would be useful. Subversive Knitting's double knitting tutorial looks excellent and helped me get a handle on the idea behind it. I can say that, based solely on my handful of swatches, I found that the gauge is much looser than straightforward knitting in the round; I was able to counteract it, though, by dropping down several needle sizes. (I think I went down three needle sizes to get something that had the sort of gauge I was looking for.)
All of that said, double knitting is a really great technique, and if you get a chance to experiment with it, you won't be sorry.
I need a bit more practice with it, but I can tell you I'm intrigued by this Knitty.com article about double-knitting a pair of socks. It seems like one heck of a challenge, don't you think?