The pattern is in 7 sizes. The smallest will fit a premature baby around 700 grams. The biggest will fit a baby born at term. The other sizes will fit babies in between.
You will need: Some 4 ply cotton. You will need 10-20 grams for every hat.
Stripes can be made to your hearts content. Only your imagination will set the limits!
Furthermore you will need double-pointed needles, 3 mm, 3.25 mm or 3.5 mm.
"Make 1"; using your right needle, lift the strand between the stitch you just knit and the next stitch, front to back. Place the stitch on the left needle and knit.
"Knit 3 together"; Slip 2 stitches together knitwise onto the right needle. Knit 1 stitch, pass the 2 slipped stitches over.
"Increases and decreases";
First doublepointed needle: Knit 1, make 1, knit 8-9-10-11-12-13-14 stitches, knit 3 together, knit 8-9-10-11-12-13-14 stitches, make 1.
Second doublepointed needle: Knit 1, make 1, knit 6-7-8-9-10-11-12 stitches, knit 3 together, knit 6-7-8-9-10-11-12 stitches, make 1.
Third doublepointed needle: Like first doublepointed needle.
Pattern: Cast on 56-62-68-74-80-86-92 stitches. Arrange the stitches with 20-22-24-26-28-30-32 stitches on first needle, 16-18-20-22-24-26-28 stitches on second needle and 20-22-24-26-28-30-32 stitches on third needle. Purl one round.
On the next round, increases and decreases begins and continues on every other round.
Knit one round with increases and decreases, purl next round and continue in this way to make a garter stitch edge. In total the edge will have 3-5 ridges, depending on your choice.
After finishing the edge, the hat is continued in stockinette stitch (knit every row, and continue increases and decreases on every other round)
Continue in this fashion, until the total number of rounds of increasing and decreasing is 8-9-10-11-12-13-14 (including the rounds that were made when knitting the edge).
Now the shaping of the hat will begin. Continue decreasing in the usual places (centre of double-pointed needles), but make no more increases.
When there are 14 stitches left, you will need to make an extra decrease at the centre back of the hat (the old increasing spot).
Continue decreasing on every other round until you have 6 stitches left. Break yarn, thread yarn through remaining stiches, tighten and weave in ends.
Straps: Using a suitable size of crochet-hook, begin at one of the 2 broader "points" at the bottom of the hat, make 50 chain-stitches. Turn and make 50 slip stitches back. Weave in ends.
Congratulations! You now finished a hat! Beware, though - they are quite addictive.....