Drusilla is a color work hat , from the bottom to the top, without seams.
The hat is worked with doubled yarn, while the initial band is worked with quadrupled yarn.
obviously if you use a fingering size yarn it will not be necessary to duplicate the yarn in the color work processing, while for the hat band you will have to double the yarn.
YARN
MYAK Tibetan Fibers, Baby Yak Lace 50 gr 380 yds/350 mt

MC Mustard 1 skein used 59.43(64, 70.40)yds / 65(70, 77) mt
CC1 Black 1 skein used 166.42(185.62, 204.82)yds / 182(203,224) mt
CC2 Chocolate 1 Skein used 32(38.40, 44.80)yds / 35(42,49) mt
NEEDLES
US 2 1/5/ 3,00 mm
US 3/ 3,25 mm
GAUGE
23 sts and 34 rnds = 4 inches (10 cm) in color work, in the round, on US 3/3,25 mm needles and doubled yarn, after blocking.
MEASUREMENTS
Circumference (unstretched): 18.89,(20.86,22.83)”/ 48,(53, 58)cm
Height 8.66”/22 cm