If you can crochet a circle you are halfway there to crocheting a hat. A hat is basically curving the yarn and increasing stitches to make it the size you want as you go around.

You basically don't want a spiral but you want to crochet a flat circle. To get the shape you make increases as you go around in order to shape the hat. One suggestion before trying to create a hat it making some flat circles to practice with. Learn the basic of crochet before attempting a project such as a hat to crochet.

Here is a basic crochet hat pattern:

Start with one Color

Using Yarn color  -  chain 2 stitches .
Round 1: Work 6 single crochet in 2nd chain from hook, place a marker for beginning of round – 6 stitches.

Round 2: *Single crochet in next stitch, 2 single crochet in next stitch *3 times – 9 stitches.

Round 3: *Single crochet in each of next 2 stitches, 2 single crochet in next stitch *3 times – 12 stitches.

Round 4: *Single crochet in each of next 2 stitches, 2 single crochet in next stitch *4 times – 16 stitches.

Round 5: *Single crochet in each of next 3 stitches, 2 single crochet in next stitch *4 times – 20 stitches.

Round 6: *Single crochet in each of next 4 stitches, 2 single crochet in next stitch *4 times – 24 stitches.

Repeat Round 6, working one more single crochet between increases on each round, until there are 36 (40, 44) stitches. Depending on the size of the hat you are crocheting.

Work 1 round even stitches.

Next Round: *Single crochet in each of next 8 (9, 10) stitches, 2 single crochet in next stitch *4 times - 40 (44, 48) stitches.

Work 1 (2, 2) rounds even.

Next Round: *Single crochet in each of next 9 (10, 11) stitches, 2 single crochet in next stitch *4 times - 44 (48, 52) stitches.

Work 3 (4, 4) rounds even. Fasten off for finished product