Here's sort of a ruth philosophy on sock knitting (or most knitting for that matter).
In the general scheme of knitting things, there are 2 kinds of knitters: those that follow directions exactly word for word, and those that fudge. I'm of the fudge sort; if I can correct a mistake without making it noticeable, then I fudge.
For anyone knitting my socks: listen up! I design these socks for my slender legs and feet, and I always need a reality check when it comes to fit, 'cause I always assume that everyone has the same dimensions as I do. I suspect that that is not the case.
But you have control over the socks at all times. For one thing, try on as you go along. Now a try-on after you've finished the ribbing will tell you exactly one thing at the moment: can you get it over your heel and around your leg. That's all it's going to tell you. As you work further down any sock, keep trying on. Remember that you've probably cast on over 2 needles (or should have), and that ribbing is stretchy. Once you get into the pattern, the stretch is not always the same as the rib. So you have to keep trying on.
If the sock so far is hugging your leg very tightly, it may not get over your heel as you progress downward, and you don't want to knit a tourniquet here. So, think about going up a needle size or more, especially if you're a tight knitter. I knit very very loosely, so again keep that in mind. If I'm using a size 0 on the socks (which is what I'm doing with the mystery ones), it's not because I want to knit a cast-iron sock; it's because the sock would be way too big for me if I knit on 2.5mm needles.
But you can change needle size as you go along. As long as the sock looks nice, and fits well, who cares what size needle you're using. You can even go up for just a section of the sock, or if you want a nice tight fit on the foot, go down a size. You're the mistress of the needles.
Oh, and I've been known to accidentally use 2 different size circular needles. And in my dpn days, I was always misplacing a needle and so went up or down for one of the needles. Yeah, this is all heresy in knitting circles, but it works.
And if you follow anyone's pattern and make a mistake at the same place every round, but you like it, don't frog it. It's now a new design.
If you need an example of my lazy knitting, consider this: on the mystery sock, I accidentally decreased the foot part 2 stitches too many, and also managed to knit the foot with a smaller needle. I did make the necessary adjustment when it came time to work the toe (which is where I discovered my goof), but the sock fits well, looks fine. Was I going to frog and entire foot and instep? Hah! I don't like working that part of the sock, so nope, it is what it is, and guess what? It fits just fine. Just encouraging you to not follow directions sometimes, or not to frog if you've done a silly mistake.
Yes, yes, I know that I post gauge. My gauge for my sock for my narrow foot and leg. If you have wide feet, you may prefer a looser gauge, otherwise the sock will cut off all circulation and you'll develop gangrene, and then they'll have to amputate your foot, and then you won't be able to run the marathon, and you'll have lots of PT and your medical bills will be high! It's better to have slightly looser gauge than gangrene, IMHO! And, if you notice, many of my charts have a combo of k1,p1,k1 on the sides. Nobody is going to care if you do k2,p1,k2 or whatever you need to make the thing fit. Just be aware that if you fool around with adding stitches, that you'll have to make a bit of an adjustment when it comes to turning the heel. but you can do it, because you are a Sock Mistress!
Knitting perfectionists will probably lob something at me, but that's their issue.
On lace, I do not fudge because it's noticeable, but on socks, especially the foot? Piffle.