Crankygrrrrrl has named this month "Frogtober" in respect to the severe amount of frogging that she, among others, has had to do this month. As I'm having a Frogtober too, and because Fuzzarelly asked about my frogging technique, I thought I'd attempt to spill the beans. Keep in mind that I learned this from countless good learn-to-knit sources and my explanation, being that of a new knitter, won't be as clear as the originals.
If you have inserted a lifeline, you can always rip back to the lifeline. Sometimes, though, you haven't bothered with the lifeline, because you're not knitting lace and it's just plain old stockinette and what could go wrong?
Yeah. So... here's what I do. I basically insert a lifeline after the fact.
What you do is to take a long circular needle, ideally a couple sizes smaller than the one you've been using, and weave it through just the right-hand leg of the V on each knit stitch on the row you want to frog back to.
Then you can just pull the main needle out and rip back with gusto! You can then knit onto your usual needle from the smaller one and things go on just fine from there.
Sometimes you will miss alignment, and go up a row at some point during the weaving-through process. Then when you frog back, you'll end up with some stitches sitting nicely on the needle, next to a bunch of little loops hopped-up (like frogs!) above the loops that are on the needle. You can either pick these up (it'll be easy, because they are firmly held in place by the needle below them), ending up with a row higher, or add a needle to the stitches just below the part that are sitting nicely, and rip back one more row.
What if it's not stockinette? As long as it's not lace, it's still reasonably possible to use this technique.
The problem is that on purl stitches, it can be a little tricky to find the appropriate next V. Here you can see me working my needle under the left-hand leg of the knit stitch V and tugging on it a little, just to see which loop is the appropriate one to pick up on the purl to the left of it. (This is 2x2 ribbing.)
If you succeed at this, it'll look something like this:
Oh, and I have reknit the poor back of my Sienna. She's just about ready for the neck split, then it's up the left front!