This is the one I use - it is worked as a spiral, so not such a problem. I just change the weight of yarn/hook size for different sizes.
Easy Crotchet Hat
Level: Easy - Intermediate (working in the round, dc, hdc, sc, sl st, basic increase)
Size: 20" circumference
Materials:
1 x 50 gm ball aran weight yarn
crochet hook in size H, or size needed for gauge + G hook if you are using Edge Option 1.
Stitch marker (to mark beginning of rnd)
Tapestry needle (or you can use crochet hook to weave in ends)
Gauge: 3.25 dc = 1" on larger hook
Abbreviations: ch- chain; dc- double crochet; dec- decrease; hdc- half double crochet; rnd- round; sc- single crochet; sk- skip; sl st- slip stitch; st(s)- stitch(es)
INSTRUCTIONS
You will work in a continuous spiral rather than joining each round with a sl st.
Ch 4.
Rnd 1: Work 10 dc in 1st ch. [11 dc]
Rnd 2: Work 2 dc in each dc around. [22 dc]
Rnd 3: (Dc in next dc, work 2 dc in next dc) around. [33 dc]
Rnd 4: (Dc in each of next 2 dc's, work 2 dc in next dc) around. [44 dc]
Rnd 5: (Dc in each of next 3 dc's, work 2 dc in next dc) around. [55 dc]
Rnd 6: Dc around.
Rnd 7: (Dc in each of next 4 dc's, work 2 dc in next dc) around. [66 dc]
Edge Option 1 (using G hook): Continue to work dc in each dc around for 3". Change to G hook (or see Option 2 below) and work dc in each dc until you have ~20" left in the ball of yarn. Work hdc in each of next 2 dc's, work 3 sc's in each of next 3 dc, work 3 sl sts in each of next dc. Fasten off.
Edge Option 2 (using st dec): Continue to work dc in each dc around for 3".
Next Rnd: (Dc in each of next 10 dc's, sk 1 dc) around. [60 dc]
Work dc in each dc until you have ~20" of yarn left.
Finish:
This is to taper off for a smooth edge and is worked over the first 8 sts only.
Work hdc in each of next 2 dc's, work 3 sc's in each of next 3 dc, work 3 sl sts in each of next dc. Fasten off. Weave in ends.