I’ve been designing a lot of socks lately and I sometimes have to stop myself from going off on a dissertation-length tangent about different ways you can modify your socks for better fit. There’s nothing wrong with including pro-tips here and there in patterns, but when you’re (well, I’m) adding paragraphs and paragraphs it starts to get beyond the scope of the pattern!
So instead I’ll share some noodling I’ve had here.
First is calf-shaping - depending on the stitch pattern, you can add calf-shaping to just about any sock. I won’t say ALL because I’m sure there’s something out there with an incredibly intricate pattern that would need a lot of massaging to make extra stitches and decreases work, but I think most patterns would allow this.
I regret not specifying this more clearly in earlier sock patterns I wrote with calf-shaping, but all extra stitches should be added to the back of the leg, rather than splitting the total stitch count evenly across instep/back of leg. This is more of an issue in cuff-down socks than toe-up, because it affects the stitch count coming into the heel section. (In toe-up, you will have already worked the heel by the time you’re adding increases for calf-shaping, so you only need to worry about centering any motifs on the back of the leg with additional stitches in the mix.)
Two hand-knit socks in light gray yarn, worked in reverse stockinette with a pattern in stockinette that looks like spooky fingers grabbing the leg. The sock on the right is in the middle of the heel flap
So if you’re knitting a cuff-down sock and want to cast on 78 stitches and decrease to 72 at the heel, you should split the stitches into 36 instep stitches and 42 back of leg stitches. That’s 6 extra stitches on the back, which will be decreased in pairs, so 3 decreases on the way to the heel and you’ll be ready to work the 72-st size heel across 34 sts as written. This means the patterning will be centered on the front and back of the sock, and you won’t need to rearrange stitches between the instep/back of leg sections before working the heel.
Next, heel flaps! The convention is to work as many rows in the flap as you have in the heel. So, a heel worked across 32 sts will be worked for 32 rows and create a nice little square. That…has never worked for me. Part of it is because my row gauge is really, really tight compared to most people, so I need to work way more rows to even get a square shape. Another part of it is even if I do get a nice square flap, that’s not actually enough length in the gusset to fit my foot!
I saw a tip…somewhere. Sock Madness? A Facebook sock knitting group? Recommending that you knit the heel flap as long as your thumb (from fingertip to the second/big knuckle). This will likely be somewhere between 2 and 3 inches. Since I’ve started doing that, my heel flap socks fit way better, and no longer get sucked underneath my foot!
If adding more rows, keep in mind you’ll need to pick up additional stitches for the gusset. For the most part, this just means you’ll keep knitting gusset decreases for longer than called for in pattern. In some cases, there might be special patterning on the sole like colorwork or riverbed decreases (google “riverbed gusset” to see what I mean), but in general more gusset stitches won’t impact the pattern.
Related to this, don’t forget to pick up stitches in the gap between the end of the heel flap and the beginning of the instep! Most patterns call for at least 1, but 2 is fine too. You might even find that one side needs more stitches than the other and end up with 19 gusset stitches on the right compared to 18 on the left - also fine! For this I’ll sometimes work a double decrease on the side with more stitches on the first round of decreases to even things up (and so I don’t have to remember which side needs an extra decrease at the end of the gusset).
Since feet aren’t always exactly the same size as calves, remember that you can tailor the fit of a sock foot by decreasing on the sole. This maintains whatever pattern on the instep but allows for a snugger fit! When you get to the toe, you have a few options to even things up in preparation for grafting.
If you have 4 or more stitches extra on the instep, send some around to the sole. For example, with 34 sts on the instep and 30 on the sole, send 1 st on either side of the instep around to the sole. Now they’re split evenly into 32!
If you have just 2 sts extra, start toe decreases a little early and work increases ONLY on the instep. For example, with 32 instep and 30 sole sts, work a decrease round only on the instep, evening them up to 30 sts each.
These are the kinds of things you learn after knitting a bunch of socks and seeing how various constructions and stitch counts fit on your foot, but I hope this helps at least one person jump start their journey into custom sock modifications!