Socks questions

[catwoman]

Hi. I was wondering if you could help me understand some of the sock forumla online steps that are out there on ravelry?

 using needle 1, pick up and knit stitches equal to one quarter of your Sock Number from the side of
your heel flap?😟
My Sock Number is 60, so I will pick up 15 stitches.?😕
Remember to pick up
1/4
of your Sock Number
rof stitches (just like with
needle 1).?🤔
Both of these should have stitches equal to a quarter of your Sock Number?
Measure your
foot from the back of your heel to the tip of your big toe (or whatever toe is longest)?
Subtract 1 1/2
inches?
repeat rnds 2 &3 until soles reaches 56,68 sts or equal to the total number of original sock stitches?

[Granny Square]

Basically, a top down heel flap sock is a simple tube with the (in your case) 60 stitches for the cuff,  a weird assembly of heel flap/turn to go around the heel that ADDS stitches to accommodate the your heel, then a gusset which SUBTRACTS those extra stitches back to the original cuff number with decreases , and a closure for the toe.  

For a heel flap construction, the total # of stitches are divided in half initially for the top of the foot (instep) and the under part of the foot.  You put the instep 'on hold' and work the underfoot part, initially on half the total sock stitches for the flap (30 in your pattern), then the heel turn; then you work down the SIDES of the turn & heel flap by picking up & knitting stitches on the sides of the stitches, then knit normally across the instep, then pick up & knit stitches across the other side of the flap and turn.  The pattern I've used starts and stops at the top/center of the 'turn', so stitches on 3 needles but some patterns may divide the needles into 4.  The reason they 'number' the needles is that you do different things with each needle (the pattern I use has a decrease near the end of needle 1, work without decreases across needle 2 (instep), decrease near the beginning of needle 3)

As far as questions on measuring your foot...once I made the first pair and got them to fit, I just measure new pairs to match another that I've made.  For the first one, I can't remember if I put them on waste yarn to see 'how much further I had to go', I think I just literally measured my foot.  So the 'measure your foot and subtract 1.5", will presumably be the spot where you start decreasing for the toe, because the x rows for the toe shaping should be 1.5".   This is similar to what I was trying to say for the 1898 hat, if you made alterations to the height you'd have to know the measurement for the depth of the # of decrease rows for the crown to start them in the right place to fit--same as a sock toe.

Your last sentence sounds like it has to do with the gusset, which usually has a round of decreases  followed by a plain round; it is telling you to repeat those rounds until you get to the same number of stitches you had before you started the heel flap.  Example, not the right numbers but let's just say:  60 for the cuff, 80-90 (wild guess) across the heel turn+heel flap sides+instep just before starting the gusset, 60 after finishing the gusset which you will work on until you need to start the toe decreases.

I'm not a huge fan of entire patterns on youtube videos, but I do use videos if I don't understand a written technique.  You might want to seek out a video on working a heel flap and gusset sock heel.