The pattern contains many photos and also internet links to my video tips.
This pattern contains written instructions with full stitch counts for every row.

Basic crochet stitches used - chain, slip stitch, single crochet, 2 single crochet into one stitch, Single crochet through the back loop (US terms).

Requirements
Yarn weight, and length:
S size
35 g / 1.24oz (84 m / 91.88 y)
first color yarn 26g / 0.92oz
(62.40m / 68.25 y)
second color yarn 9 g / 0.32oz
(21.60 m / 23.63 y)
M size
53 g / 1.87oz (127.20 m / 139.12 y)
first color yarn 43 g / 1.52oz
(103.20 m / 112.87 y)
second color yarn 10 g / 0.35oz
(24 m / 26.25 y)
L size
71 g / 2.51oz (170.40 m / 186.36 y)
first color yarn 60 g / 2.12oz
(144 m / 157.48 y)
second color yarn 11g / 0.39oz
(26.40 m / 28.88 y)

Approximate measurements of the hat when it is finished
S size
Head girth 25 – 27cm / 9⅞ – 10⅝in
Head height 10cm / 3⅞in
Neck
circumference 21 – 23cm / 8¼ – 9in

M size
Head girth 31 – 33cm / 12⅛ – 13in
Head height 12cm / 4¾in
Neck
circumference 25 – 27cm /9⅞ – 10⅝in

L size
Head girth 36 – 38cm / 14⅛ – 14⅞in
Head height 13cm / 5⅛in
Neck
circumference 32 – 34cm / 12⅝ –13⅜in