Pattern for border:

cast on 4 st
row 1: k1, yo, k2tog, yo, k1
row 2: knit
row 3: k2, yo, k2tog, yo, k1
row 4: knit
row 5: k3, yo, k2tog, yo, k1
row 6: knit
row 7: k4, yo, k2tog, yo, k1
row 8: cast off 4st, knit to end
repeat rows 1-8 until required length then sew onto blanket.

Pattern for blanket:

(I cast on 99 stitches (or multiples of 3 for a bigger/smaller blanket), DK on 5mm needles, for a pram/moses basket/car seat/pushchair sized blanket.)

18 rows of garter stitch alternating with

18 rows of pattern:

row 1: k1, yo, k2tog to end
row 2: k1, yo, k2tog to end
row 3: knit
row 4: purl

Knit these 4 rows four times (16 rows), then knit row 1 and row 2 one more time making a total of 18 rows in pattern.