I knit the cuff 1-1/2” long.
I modified Round 3 of the Feather and Fan pattern for the leg so that the decreases would angle towards each other (plus match the pictures) instead of all being in the same direction on needles 1 and 2 as follows -
(K2tog) 3 times, (yo, k1) 6 times, (ssk) 3 times; repeat once more.
10 repeats of the pattern is 3-1/2” long. I worked 13 reps of the pattern. The cuff and leg are 6” long.
I made some modifications to adapt it to magic loop working taat.
On the decrease round just before working the heel flap I worked needles 1 and 2 as follows -
K1, k2tog, k12, ssk, k1; repeat 1 more time. This lined up better with previous rounds.
I’ll work the heel flap and the heel turn on needle 1, leaving needle 2 for the instep.
I changed the first row and left the second row the same -
Row 1 - Sl1, k1 to end of row.
Row 2 - Sl1, p to end of row.
The directions state to work these two rows 29 times, ending on a knit row; however the first row of the heel turn starts with a knit row so I’ll knit an even number of rows.
After 30 rows the heel flap is 2-3/8” long. I’m going to make it a little bit longer. After 36 rows the heel flap is 2-3/4” long. Perfect! 
Worked the heel flaps taat, then worked the first heel turn to picking up the gusset sts for the first needle on the first round on the first sock. Now to work the second sock to the same point, then back to knitting in-the-round.
I had 9 sts on each side of the centre marker after finishing the heel turn and picked up 17 sts on the gusset. I’m going to put all the heel and gusset sts on needle 1 and the instep sts on needle 2, keeping the beginning of the round at the centre of the heel. I have 26 sts and need to decrease to 16 sts on each side of the centre marker so I need to decrease 10 sts/side.
After picking up the first gusset sts, you knit across the instep so this equals Round 1 of the Modified Feather and Fan pattern for the instep. So Round 1 of the decrease round is Round 2 of the Modified Feather and Fan pattern.
I changed Round 3 of the Modified Feather and Fan pattern to keep the angles of the decreases the same as the previous pattern -
Round 3 - (K2tog) 2 times, (yo, k1) 5 times, (ssk) 3 times, (k2tog) 3 times, (yo, k1) 5 times, (ssk) 2 times.
Round 1 started in the middle of the heel. Now that the decreases are done I changed the beginning of the round to the instep needle, now called needle 1. 
Because of reducing the sts to 64 from 72, these just fit because of my really high instep. The gauge relaxes slightly after machine washing and drying, which should be just enough.
After 14 instep patterns the foot is 7” long. 13 reps was a little too short to stop.
For the toe shaping I adapted the decrease rounds to -
Round 1 (needles 1 and 2) - K1, ssk, knit to last 3 sts, k2tog, k1.
Round 2 (needles 1 and 2) - Knit.
I stopped decreasing when I had 10 sts/needle. My toes are wider so I need slightly more sts to fit better.
I’m going to graft the toes, weave in the ends, duplicate stitch on each side where you switch from knitting in-the-round to the heel flap, weigh and measure them plus take pictures tomorrow.
The socks used 71.9g (286.2m/313.5y). Before blocking the leg is 9” long to the bottom of the heel flap x 7-1/2” in circumference. The foot is 9” long x 7-3/4” in circumference.
After blocking the leg is 8-1/2” long to the bottom of the heel flap x 7-1/2” in circumference. The foot is 8-3/4” long.
The balls weighed 48.4g and 47.4g = 95.8g.