Yarn: 3 oz worsted weight. The example was done with Bernat Cottontots yarn, a soft cotton yarn perfect for a summer sun hat.
Circular Needles, Size 9 US (5.5 mm), 16″ long. I recommend 16″ Addi Turbo Circular Knitting Needles (the best!) or TAKUMI VELVET CIRCULAR KNITTING NEEDLES 16-SIZE 9 (bamboo works well with cotton yarn)
Double pointed needles, size 9 US, 5.5 mm. I recommend 7 Inch Clover Takumi Bamboo Premium Double Point Knitting Needles
Stitch markers. I prefer flat, soft stitch markers like Soft Stitch Ring Markers – 30/Pkg because they don’t break or get tangled up in the yarn.
Gauge: about 4 st per 1 in (or about 8 st per 5 cm)
Round 1: Slip first stitch. Knit to last stitch. Knit last stitch with slipped first stitch, being careful not to twist the row. This will close the round and decrease one stitch. 126 st. Place marker.
Round 2: Purl. This forms a neat edge for the scallops.
Round 3: * k1, (k2tog 3 times), ([yo, k1] 5 times), yo 1, (k2tog tbl 3 times), rep from *
Round 4-6: Knit.
Repeat rounds 3-6 twice.
Round 15 (decrease to end ruffle): k2tog, k1. 84 st.
I suggest moving the stitch markers to every 12 stitches. This will help you track the decreases later.
Switch to double pointed needles at the beginning of the decrease or whenever it becomes difficult to knit on the circular needles. I just knit off an equal number of stitches on to the double pointed neeedles on the first decrease round.
Round 1: (k10, k2tog) around. 77 st.
Round 2 and all even rows: Knit.
Round 3: (k9, k2tog) around. 70 st.
Round 5: (k8, k2tog) around. 63 st.
Round 7: (k7, k2tog) around. 56 st.
Round 9: (k6, k2tog) around. 49 st.
Round 11: (k5, k2tog) around. 42 st.
Round 13: (k4, k2tog) around. 35 st.
Round 15: (k3, k2tog) around. 28 st.
Round 17: (k2, k2tog) around. 21 st.
Round 19: (k1, k2tog) around. 14 st.
Round 21: k2 tog around. 7 st.
Cut the yarn leaving about 6″ tail. Using a tapestry needle, thread the tail through the remaining stitches. Pull stitches together tightly. Thread tail through hole in crown. Draw crown closed securely by pulling tail. Weave the tail and all other ends through stitches on wrong side.
Finished measurements: Hat body about 20″ in circumference. 8-9″ from ruffle to crown.
Increase or decrease in multiples of 18 for the pattern of the ruffle. You will need to adjust the decrease for your total number of stitches.