Is the shaker on top of the container clogged? Usually you can remove the top. Be careful, though, you don't want to spill glitter everywhere. Then rinse the top of the container to unclog the part that allows glitter to flow freely out. You could also try some compressed air to blow the glitter out. There shouldn't be a lot stuck in the top. You can probably sweep it up easily.
Hi! I use a straight pin to clear clogs.
You could use a toothpick to poke through the holes.
Hello. Cindy here. I recommend doing this job outside. Clean the clog out using an old toothbrush and then replace it and then glitter away.