It’s finally time! Hooray!
First, a small bit of math to figure out how many to cast on. First, look at the ankle and foot circumference measurements. If they are within ½ inch of one another, we’ll use the smaller of the two. Socks need “negative ease“, so we don’t want the bigger number unless it’s a LOT bigger. If the difference between ankle and foot circumference is greater than ½ inch, use the ankle measurement alone. Take that number and multiply it by 0.9 (to get the negative ease), then multiply that by your stitch gauge (stitches/inch). Round the results it to the nearest whole number.
Ankle or foot measurement (whichever is smaller)___________ x ___________ sts/in ≈ ___________ sts for cuff
If you’re lucky, this number is exactly what you need for your stitch pattern to work out. Say you want to do k2p2 ribbing for the cuff and your math gave you a number divisible by 4 – that’s LUCK!! Most likely, it’s not. So, round it again. In most cases, you want to round down to the necessary number of stitches, but if the stitch is particularly inflexible, you may need to round up.
Tomorrow: techniques for casting on