Details of the bookmark pattern go as follows:
Yarn colours: Yellow, White and Green
Stitches: Single crochet (sc), Chain (ch) and Cluster Stitch (cs)

The cluster stitch in this project is a three double crochet cluster.

The instructions of the cluster stitch are given separately.

Cluster stitch: Yarn over, insert hook in stitch, yarn over and pull hook out of the stitch. We will have three loops on the hook. Yarn over and pull yarn through two loops. Repeat twice. We will now have 4 loops on the hook. Yarn over and pull through all four loops.