Roll up fondant into pearls,let dry a couple of hours, drop in a container and shake with pearl dust. Easy, Easy.
If you are a stickler about size you can roll the fondant out to an even thickness then use the back of tips, small medium and large to "punch out" pieces of fondant to roll.
That's how I do it! I think there are some articles on this site on how to make them as well. I know you can google it too for detailed instructions with photos.
Only thing.......... make sure you give yourself enough time to do it because the first time I had to make them I thought Oh, I can make them in 30 minutes. WRONG!!!
Try a couple of hours when you need 300-400 of them.