the pattern comes in several sizes, from newborn to 24 months. it has instructions how to make a rounded bonnet just like this one.

gauge - 21 stitches 10cm/4inches over stockinette stitch.

Recommended yarn: any to obtain the gauge. DK for regular look, or thinner yarn on larger needles for daintier look.
Recommended needle size: to obtain the gauge. Your needle size might vary depending on how tight or loose your knitting is. Please be sure to make a gauge swatch to make sure you obtain the gauge. For most, 4mm needles work the best.

You will need: yarn (up to 40g for the smallest sizes, up to 80g for the larger sizes), knitting needles, darning needle to weave in the yarn ends and to sew the back of the bonnet. Crochet hook in the same mm size as the knitting needles to make the ties (if you are making crochet ties).
in the pattern there are two ways to make the ties, knit and crochet version. there also are directions to make longer ties.

The bonnet is knit flat.

the measurements in the pattern are given in both centimeters and inches.