Evanesce Hat - Worsted - Multiple Sizes

I love fades, and they always make me thing of things dissipating or disaperating, especially with speckled/kettle dyed yarn. Hence, the name Evanesce (to dissipate into vapor). 
If you are like me, you have extra worsted weight yarn around "just in case." This stash-busting pattern allows you to use them and look good while doing it! (Mine has a mix of Cascade 220, Malabrigo Rios, and Berocco Vintage.)
You will be holding two worsted yarns together at all times, and will end up switching out every 4-7 rows. If your leftovers are little over or under - Never fear! You will still be able to get the same effect by switching 1/2-1 1/2 rows early or late. 
It is possible to get one of each size (4 hats) out of 5 full skeins of 192 meters (210 yards), but your last hat may have more of the first and last colors in it due to how much yarn is used. I used 5 skeins of Malabarigo Rios for the pink/green samples. 
Note: Be sure to cake the yarn so that you have access to both ends for the fade effect to work. 

Sizes: 
Small: 16-17" head
Medium: 18-20" head
Large: 21-22" head
X-Large: 23+" head

Yarn Weight: Two strands of worsted weight held together = Bulky 

Gauge: 14 stitches and 24 rows = 10cm in Seed Stitch

Needle Size: US8 - 5.0mm & US 10 - 6.0mm

Yarn Amount Needed: 200-250m (219-273 yards)