Don’t do this method unless you have the patience to wrangle multiple balls of yarn as you would with stranded knitting. The difference is that with stranded knitting, your yarn balls are all different colors whereas with this method of helix knitting, you have multiple balls of yarn that are the same color.

This is a free pattern so I’m not giving away too much information with the following notes.
After knitting the band, the pattern is a repeat of 5 purl rows and 4 knit rows. To knit the Wurm as a true helix you must have a small ball of yarn for each one of those nine rows.

So in this case I had 5 small balls of yellow and 4 small balls of black.
I wound them as a center pull so they wouldn’t bounce around too much ( you could also place each ball in its own little baggie) and lined them up in an elongated basket so that every time I picked up the next yarn, I would put that ball at the top end of the basket to minimise tangling the yarns.

After knitting the band with size 5 (3.75mm) needles, I switched to size 7 (4.5mm) needles and worked around the first row starting each ball at about every 11th stitch. This is important. All the colors are started on that first row after the band so that each color stacks up properly on every subsequent row. First I added in the yellow yarns in purl stitch and then added in the black yarns with knit stitch. I worked the first row of yellow on top of the black as a knit stitch to avoid getting yellow blips on the public side of the hat.

The hat will look a little different at the base near the band because the nature of helix knitting means that each block of purl and knit stitches will gradually taper to full width instead of being full thickness right from the start. However the poofy nature of the purl stitches tends to hide the taper and make it less obvious.

The hat weighed 74 g when complete.
I worked a total of 7 rows of yellow and 7 rows of black + the double yellow band at the base and the decrease black rows at the top.

Band is 26 rows of yellow
Body of hat is approx 35rows of yellow 32 rows of black

I do have some left over small yarn balls that I could make into a pompon for the hat.