Needle 2.0 for board, heel and toe
Needle 2.5 for the rest of the sock
MC=Black CC=Apple green
The squares in the original pattern are 8 stitches x 9 rows, I used 6 stitches x 7 rows, so 1x total pattern is 14 rows.

Board
CO 60 stitches with (double) needle 2.0 in MC
*K1tbl, P1* for 15 rows
Change to needle 2.5, knit 1 row in MC
Knit pattern 4 times (56 rows)

Heel
Change to needle 2.0

Heel flap
(RS) Knit 30 stitches in MC
R1: (WS) K3, P24, K3
R2: (RS) K3, *slip 1, K1*, repeat until 3 stitches left, K3
R3: (WS) K3, P24, K3
R4: (RS) K3, *K1, slip 1*, repeat until 3 stitches left, K3
Repeat R1-R4 7 times
(WS) K3, P24, K3

Heel
(RS) K17, SSK, K1, turn
(WS) Slip 1, P5, K2tog, P1, turn
(RS) Slip 1, K6, SSK, K1, turn
(WS) Slip 1, P7, K2tog, P1, turn
(RS) Slip 1, K8, SSK, K1, turn, etcetera increasing 1 stitch until 18 stitches left, last needle is on (WS)

Foot
Change to needle 2.5
Knit 9 stitches in MC (until central back), continue knitting in pattern starting the chart in the exact middle of row 1!
Pick up (in pattern!) 15 stitches on both sides of the heel flap + 1 extra stitch (tbl) to prevent hole between sole and instep.
Continue knitting in pattern decreasing 1 stitch on both sides of the sole (K2tog, K1 on left side / K1, SSK on right side) every other needle for 10 times.
Knit pattern 3 times (6 blocks), knit 7 extra rows in pattern (1 block).

Toe
Change to needle 2.0, knit 1 row in MC, cut CC, place markers (LM, RM) between sole and instep. Decrease for toe as follows (rows start at central back):

• R1, R5, R8, R11, R13, R15, R17, R18-R23: Knit until 3 stitches before LM, K2tog, K1, slip LM, K1, SSK, knit until 3 stitches before RM, K2tog, K1, slip RM, K1, SSK, knit until end of row (central back)
• All other rows: Knit

With the last 8 stitches: turn sock inside out, divide the 8 stitches over 2 needles and with a third needle knit and BO the stitches together. Weave in loose ends, knit second sock as the first.