Cut three circles, a fabric circle approx 9 cm across, then two felt circles each a bit smaller than before.
using bonda web, or wonder under, or some other magic adhesive, cut out some numbers of a contrasting fabric and stick them centrally onto the fabric circle.
sew tiny seed beads all over the numbers to make them sparkly.
turn over and sew a running stitch around the edge. I tend to use a doubled thread for this so that when you pull it tight it's less likely to snap.
cut a circle of card that will be the final size of the badge. I cut a 5cm circle of card.
layer the fabric beaded side down, the larger piece of felt, and then the piece of card.
pull the running stitches tight, to gather the fabric around the card.