You can use one color of yarn, two colors of yarn or three colors of yarn for crocheting this hat. This hat is loose at the top. If you want to crochet a hat with three stripes, you should use a thicker yarn. If you want to crochet lightweight summer hat you should use DK weight yarn and crochet loosely.

Material and tools:
100 g of Main Color light worsted weight yarn LANOSO ALARA, 50%cotton, 50% acrylic, 140m/50g;
50 g of Contrasting Color 1 and Contrasting Color 2 only light worsted weight yarn LANOSO ALARA, 50% cotton, 50% acrylic, 140m/50g;
Crochet hook size 4 mm(G); hook size 3 mm(D) hook size 5 mm(H);
line for beading (nylon), diameter 0.3 mm.
You can use any light worsted or DK weight yarn approx. 140m/50g. You can use multiple strands of the yarns to make up a single strand of light worsted or DK weight approx. 140m/50g.

Now pattern is tested in the group. Perhaps the corrections will be.