I knitted this example using Estelle Yarns Alpaca Merino Chunky. With this being a stranded pattern, this makes for a very warm hat. The original pattern is a snug adult medium. For an adult large, use the instructions in brackets (noting that there is a slight variation in the patterns).

With the bulky weight yarn, this pattern knits up very quickly. Make sure to leave enough slack in the yarn as you strand to avoid puckering and to ensure a good fit.