for the bonnet:
No Sew Bear Ears Bonnet in newborn and sitter/6-12m size
Gauge: 21 st in 4in/10cm in stockinette stitch.

Recommended yarn: any to obtain the gauge. DK or Fingering 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, 4.5mm needles work the best.
You will need: yarn, knitting needles, darning needle to weave in the yarn ends and to sew the back of the bonnet.
The bonnet is knit flat.

for the romper:
in newborn and sitter/6-12m size
Gauge: 20 stitches in 4in/10cm in 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. for most, 4mm work the best. 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.
You will need: yarn, knitting needles, cable needle, five buttons, darning needle or crochet hook to weave in the yarn ends, two stitch holders or scrap yarn, stitch marker, sewing needle and matching thread to sew on the buttons.
Upper part of the romper is knit flat, but the bottom part and sleeves are knit in the round.

all the measurements in the patterns are given in both inches and centimeters.