US terminology.
I used regular pony beads for this bag.
Ch 2 counts as dc throughout.
Can be increased in size by making beginning circle larger.
Can use any number color of beads. If you want a complete spectrum of colors, divide the number of colors by the number of stitches of the end increase row.

Gauge not important.

Made in the round, slip stitching at the end of each round.
Mc-magic circle
Dc-double crochet
Hdc-half double crochet
Sl-slip stitch
Rep around-repeat around
Sc-single crochet
Yo-yarn over

Please let me know if you have any questions.