From The Last Stitch:
Ullvi is the perfect pattern for a slightly slouchy fit, or if you are using a fabric with less give and stretch. Easy to adjust after your preferences, this PDF sewing pattern can be turned into both a chunky ski hat or a skull cap to wear during cold-weather workouts. For a more fitted watch cap style, we recommend the Brisa Beanie Pattern instead.
S (53 cm | 21")
M (56 cm | 22 1/8")
L (60 cm | 23 5/8")
Size range includes adults and children. This pattern is slightly fitted but not tight.
Knits with stretch, stretchy fleece, sweater knits and rib knits with Spandex are great options. The fabric should have at least 50% stretch. Refashioned sweaters with a ribbed hem can also be used to make this pattern.
►Length: 0.75 m/0.8 yards | Width (S-L): 49-57 cm/19.5-22.5"