Coffee Mug or Teacup Cozy Crochet Pattern

This coffee cup cozy is a combination of 2 patterns I found.
The cluster stitch is taken from this bookmark pattern.
The coffee mug cozy idea is taken from this website.

Dimensions:
About 9 inches around (stretched out) and 3 inches tall.
The flap is about 2" long
Cluster: Insert your hook into the specified stitch (or stitch space) yarn over and pull up one loop (2 loops on the hook), yarn over the hook and insert your hook into the same specified stitch (or stitch space), yarn over and pull up one loop (4 loops on the hook). Yarn over and pull through all 4 loops on the hook.

Make a chain about 9" long,
Starting in 2nd ch from hook, crochet *cluster, ch1* across at the beginning of the next row, ch 1, turn, and continue pattern.
Crochet rows until approximately 3 inches tall, then finish off.
For flap: in second color, 1/3 of the way down side, make 6 dc.
ch 2, turn, dc across - until desired length. (I made my flap about 2" long) Finish off
Add button.