This is my DK beanie hat pattern I have included sizes for up to a 66cm (approx 26in) circumference so should be big enough to fit very large heads. Make sure to measure before starting to get the best fit.
 
This pattern includes written instructions on how to include any of my Instarsia charts on the front.
 
UK DK = US DK = AU 8ply
22 sts and 28 rows to 10cm, (4in) over stocking stitch on 4mm needles or the size required to give correct tension. Check your tension - if less stitches use a thinner needle, if more use a thicker needle.
 
Sizes Circumfrance: 
48, 50, 54, 58, 62, 66 CM 
(19,  19¾, 21¼, 22¾, 24½, 26)in