Find below a pattern for a knitted leaf to get you going. Pattern designed by me- feel free to use, share and adapt.

Leaf Pattern

Abbreviations
St(s) – stitch(es)
K – Knit
Yo- Yarn over needle
P – Purl
Ssk – knit two together
K2tog - Slip, Slip, Knit - slip one stitch as if to knit, slip another stitch as if to knit, stick point of left needle in two slipped stitches in front of the right needle and knit.

Cast on 3 stitches.
Stocking stitch 4 rows (or make a 3 stitch i cord for 1cm)
Row 5: K1, yo, k1, yo, k1 – 5 sts
Row 6 and all even rows: Purl
Row 7: K2, yo, K1, Yo, k2 – 7 sts
Row 9: K3, yo, K1, yo, K3 – 9 sts
Row 11: K4, yo, K1, yo, K4 – 11 sts
Row 13: K5, yo, K1, yo, K5 – 13 sts
Row 15: K6, yo, K1, yo, K6 – 15 sts
Row 17: K7, yo, K1, yo, K7 – 17 sts
Row 19: K1, Ssk, K5, yo, K1, yo, k5, k2tog, k1- 17 sts
Row 21: K1, Ssk, K5, yo, K1, yo, k5, k2tog, k1 – 17 sts
Row 23: k1, ssk, k4, K1, k4, k2tog, k1 – 15 sts
Row 25: K1, ssk, k3, K1, k3, k2tog, k1 – 13 sts
Row 27: k1, ssk, k2, K1, k2, k2tog, k1 – 11 sts
Row 29: k1, ssk, k1, k1, k1, k2tog, k1 – 9 sts
Row 31: k1, ssk, K1, k2tog, k1 – 7 sts
Row 33: k1, ssk, k1, k2tog, k1- 5 sts
Row 35: ssk, k1, k2tog – 3 sts
Row 37: k3tog
Fasten off